]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - net/bluetooth/smp.c
projects / mirror_ubuntu-bionic-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
s390/speculation: Support 'mitigations=' cmdline option
[mirror_ubuntu-bionic-kernel.git] / net / bluetooth / smp.c
1 /*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License version 2 as
7 published by the Free Software Foundation;
8
9 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17
18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
20 SOFTWARE IS DISCLAIMED.
21 */
22
23 #include <linux/debugfs.h>
24 #include <linux/scatterlist.h>
25 #include <linux/crypto.h>
26 #include <crypto/algapi.h>
27 #include <crypto/b128ops.h>
28 #include <crypto/hash.h>
29 #include <crypto/kpp.h>
30
31 #include <net/bluetooth/bluetooth.h>
32 #include <net/bluetooth/hci_core.h>
33 #include <net/bluetooth/l2cap.h>
34 #include <net/bluetooth/mgmt.h>
35
36 #include "ecdh_helper.h"
37 #include "smp.h"
38
39 #define SMP_DEV(hdev) \
40 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data)
41
42 /* Low-level debug macros to be used for stuff that we don't want
43 * accidentially in dmesg, i.e. the values of the various crypto keys
44 * and the inputs & outputs of crypto functions.
45 */
46 #ifdef DEBUG
47 #define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
48 ##__VA_ARGS__)
49 #else
50 #define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
51 ##__VA_ARGS__)
52 #endif
53
54 #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
55
56 /* Keys which are not distributed with Secure Connections */
57 #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY);
58
59 #define SMP_TIMEOUT msecs_to_jiffies(30000)
60
61 #define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \
62 0x3f : 0x07)
63 #define KEY_DIST_MASK 0x07
64
65 /* Maximum message length that can be passed to aes_cmac */
66 #define CMAC_MSG_MAX 80
67
68 enum {
69 SMP_FLAG_TK_VALID,
70 SMP_FLAG_CFM_PENDING,
71 SMP_FLAG_MITM_AUTH,
72 SMP_FLAG_COMPLETE,
73 SMP_FLAG_INITIATOR,
74 SMP_FLAG_SC,
75 SMP_FLAG_REMOTE_PK,
76 SMP_FLAG_DEBUG_KEY,
77 SMP_FLAG_WAIT_USER,
78 SMP_FLAG_DHKEY_PENDING,
79 SMP_FLAG_REMOTE_OOB,
80 SMP_FLAG_LOCAL_OOB,
81 SMP_FLAG_CT2,
82 };
83
84 struct smp_dev {
85 /* Secure Connections OOB data */
86 u8 local_pk[64];
87 u8 local_rand[16];
88 bool debug_key;
89
90 u8 min_key_size;
91 u8 max_key_size;
92
93 struct crypto_cipher *tfm_aes;
94 struct crypto_shash *tfm_cmac;
95 struct crypto_kpp *tfm_ecdh;
96 };
97
98 struct smp_chan {
99 struct l2cap_conn *conn;
100 struct delayed_work security_timer;
101 unsigned long allow_cmd; /* Bitmask of allowed commands */
102
103 u8 preq[7]; /* SMP Pairing Request */
104 u8 prsp[7]; /* SMP Pairing Response */
105 u8 prnd[16]; /* SMP Pairing Random (local) */
106 u8 rrnd[16]; /* SMP Pairing Random (remote) */
107 u8 pcnf[16]; /* SMP Pairing Confirm */
108 u8 tk[16]; /* SMP Temporary Key */
109 u8 rr[16]; /* Remote OOB ra/rb value */
110 u8 lr[16]; /* Local OOB ra/rb value */
111 u8 enc_key_size;
112 u8 remote_key_dist;
113 bdaddr_t id_addr;
114 u8 id_addr_type;
115 u8 irk[16];
116 struct smp_csrk *csrk;
117 struct smp_csrk *slave_csrk;
118 struct smp_ltk *ltk;
119 struct smp_ltk *slave_ltk;
120 struct smp_irk *remote_irk;
121 u8 *link_key;
122 unsigned long flags;
123 u8 method;
124 u8 passkey_round;
125
126 /* Secure Connections variables */
127 u8 local_pk[64];
128 u8 remote_pk[64];
129 u8 dhkey[32];
130 u8 mackey[16];
131
132 struct crypto_cipher *tfm_aes;
133 struct crypto_shash *tfm_cmac;
134 struct crypto_kpp *tfm_ecdh;
135 };
136
137 /* These debug key values are defined in the SMP section of the core
138 * specification. debug_pk is the public debug key and debug_sk the
139 * private debug key.
140 */
141 static const u8 debug_pk[64] = {
142 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
143 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
144 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
145 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
146
147 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
148 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
149 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
150 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
151 };
152
153 static const u8 debug_sk[32] = {
154 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
155 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
156 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
157 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
158 };
159
160 static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
161 {
162 size_t i;
163
164 for (i = 0; i < len; i++)
165 dst[len - 1 - i] = src[i];
166 }
167
168 /* The following functions map to the LE SC SMP crypto functions
169 * AES-CMAC, f4, f5, f6, g2 and h6.
170 */
171
172 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m,
173 size_t len, u8 mac[16])
174 {
175 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
176 SHASH_DESC_ON_STACK(desc, tfm);
177 int err;
178
179 if (len > CMAC_MSG_MAX)
180 return -EFBIG;
181
182 if (!tfm) {
183 BT_ERR("tfm %p", tfm);
184 return -EINVAL;
185 }
186
187 desc->tfm = tfm;
188 desc->flags = 0;
189
190 /* Swap key and message from LSB to MSB */
191 swap_buf(k, tmp, 16);
192 swap_buf(m, msg_msb, len);
193
194 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
195 SMP_DBG("key %16phN", k);
196
197 err = crypto_shash_setkey(tfm, tmp, 16);
198 if (err) {
199 BT_ERR("cipher setkey failed: %d", err);
200 return err;
201 }
202
203 err = crypto_shash_digest(desc, msg_msb, len, mac_msb);
204 shash_desc_zero(desc);
205 if (err) {
206 BT_ERR("Hash computation error %d", err);
207 return err;
208 }
209
210 swap_buf(mac_msb, mac, 16);
211
212 SMP_DBG("mac %16phN", mac);
213
214 return 0;
215 }
216
217 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32],
218 const u8 v[32], const u8 x[16], u8 z, u8 res[16])
219 {
220 u8 m[65];
221 int err;
222
223 SMP_DBG("u %32phN", u);
224 SMP_DBG("v %32phN", v);
225 SMP_DBG("x %16phN z %02x", x, z);
226
227 m[0] = z;
228 memcpy(m + 1, v, 32);
229 memcpy(m + 33, u, 32);
230
231 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
232 if (err)
233 return err;
234
235 SMP_DBG("res %16phN", res);
236
237 return err;
238 }
239
240 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32],
241 const u8 n1[16], const u8 n2[16], const u8 a1[7],
242 const u8 a2[7], u8 mackey[16], u8 ltk[16])
243 {
244 /* The btle, salt and length "magic" values are as defined in
245 * the SMP section of the Bluetooth core specification. In ASCII
246 * the btle value ends up being 'btle'. The salt is just a
247 * random number whereas length is the value 256 in little
248 * endian format.
249 */
250 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
251 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
252 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
253 const u8 length[2] = { 0x00, 0x01 };
254 u8 m[53], t[16];
255 int err;
256
257 SMP_DBG("w %32phN", w);
258 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
259 SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
260
261 err = aes_cmac(tfm_cmac, salt, w, 32, t);
262 if (err)
263 return err;
264
265 SMP_DBG("t %16phN", t);
266
267 memcpy(m, length, 2);
268 memcpy(m + 2, a2, 7);
269 memcpy(m + 9, a1, 7);
270 memcpy(m + 16, n2, 16);
271 memcpy(m + 32, n1, 16);
272 memcpy(m + 48, btle, 4);
273
274 m[52] = 0; /* Counter */
275
276 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
277 if (err)
278 return err;
279
280 SMP_DBG("mackey %16phN", mackey);
281
282 m[52] = 1; /* Counter */
283
284 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
285 if (err)
286 return err;
287
288 SMP_DBG("ltk %16phN", ltk);
289
290 return 0;
291 }
292
293 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16],
294 const u8 n1[16], const u8 n2[16], const u8 r[16],
295 const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
296 u8 res[16])
297 {
298 u8 m[65];
299 int err;
300
301 SMP_DBG("w %16phN", w);
302 SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
303 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
304
305 memcpy(m, a2, 7);
306 memcpy(m + 7, a1, 7);
307 memcpy(m + 14, io_cap, 3);
308 memcpy(m + 17, r, 16);
309 memcpy(m + 33, n2, 16);
310 memcpy(m + 49, n1, 16);
311
312 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
313 if (err)
314 return err;
315
316 SMP_DBG("res %16phN", res);
317
318 return err;
319 }
320
321 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32],
322 const u8 x[16], const u8 y[16], u32 *val)
323 {
324 u8 m[80], tmp[16];
325 int err;
326
327 SMP_DBG("u %32phN", u);
328 SMP_DBG("v %32phN", v);
329 SMP_DBG("x %16phN y %16phN", x, y);
330
331 memcpy(m, y, 16);
332 memcpy(m + 16, v, 32);
333 memcpy(m + 48, u, 32);
334
335 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
336 if (err)
337 return err;
338
339 *val = get_unaligned_le32(tmp);
340 *val %= 1000000;
341
342 SMP_DBG("val %06u", *val);
343
344 return 0;
345 }
346
347 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16],
348 const u8 key_id[4], u8 res[16])
349 {
350 int err;
351
352 SMP_DBG("w %16phN key_id %4phN", w, key_id);
353
354 err = aes_cmac(tfm_cmac, w, key_id, 4, res);
355 if (err)
356 return err;
357
358 SMP_DBG("res %16phN", res);
359
360 return err;
361 }
362
363 static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16],
364 const u8 salt[16], u8 res[16])
365 {
366 int err;
367
368 SMP_DBG("w %16phN salt %16phN", w, salt);
369
370 err = aes_cmac(tfm_cmac, salt, w, 16, res);
371 if (err)
372 return err;
373
374 SMP_DBG("res %16phN", res);
375
376 return err;
377 }
378
379 /* The following functions map to the legacy SMP crypto functions e, c1,
380 * s1 and ah.
381 */
382
383 static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r)
384 {
385 uint8_t tmp[16], data[16];
386 int err;
387
388 SMP_DBG("k %16phN r %16phN", k, r);
389
390 if (!tfm) {
391 BT_ERR("tfm %p", tfm);
392 return -EINVAL;
393 }
394
395 /* The most significant octet of key corresponds to k[0] */
396 swap_buf(k, tmp, 16);
397
398 err = crypto_cipher_setkey(tfm, tmp, 16);
399 if (err) {
400 BT_ERR("cipher setkey failed: %d", err);
401 return err;
402 }
403
404 /* Most significant octet of plaintextData corresponds to data[0] */
405 swap_buf(r, data, 16);
406
407 crypto_cipher_encrypt_one(tfm, data, data);
408
409 /* Most significant octet of encryptedData corresponds to data[0] */
410 swap_buf(data, r, 16);
411
412 SMP_DBG("r %16phN", r);
413
414 return err;
415 }
416
417 static int smp_c1(struct crypto_cipher *tfm_aes, const u8 k[16],
418 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
419 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
420 {
421 u8 p1[16], p2[16];
422 int err;
423
424 SMP_DBG("k %16phN r %16phN", k, r);
425 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra);
426 SMP_DBG("preq %7phN pres %7phN", preq, pres);
427
428 memset(p1, 0, 16);
429
430 /* p1 = pres || preq || _rat || _iat */
431 p1[0] = _iat;
432 p1[1] = _rat;
433 memcpy(p1 + 2, preq, 7);
434 memcpy(p1 + 9, pres, 7);
435
436 SMP_DBG("p1 %16phN", p1);
437
438 /* res = r XOR p1 */
439 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
440
441 /* res = e(k, res) */
442 err = smp_e(tfm_aes, k, res);
443 if (err) {
444 BT_ERR("Encrypt data error");
445 return err;
446 }
447
448 /* p2 = padding || ia || ra */
449 memcpy(p2, ra, 6);
450 memcpy(p2 + 6, ia, 6);
451 memset(p2 + 12, 0, 4);
452
453 SMP_DBG("p2 %16phN", p2);
454
455 /* res = res XOR p2 */
456 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
457
458 /* res = e(k, res) */
459 err = smp_e(tfm_aes, k, res);
460 if (err)
461 BT_ERR("Encrypt data error");
462
463 return err;
464 }
465
466 static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16],
467 const u8 r1[16], const u8 r2[16], u8 _r[16])
468 {
469 int err;
470
471 /* Just least significant octets from r1 and r2 are considered */
472 memcpy(_r, r2, 8);
473 memcpy(_r + 8, r1, 8);
474
475 err = smp_e(tfm_aes, k, _r);
476 if (err)
477 BT_ERR("Encrypt data error");
478
479 return err;
480 }
481
482 static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16],
483 const u8 r[3], u8 res[3])
484 {
485 u8 _res[16];
486 int err;
487
488 /* r' = padding || r */
489 memcpy(_res, r, 3);
490 memset(_res + 3, 0, 13);
491
492 err = smp_e(tfm, irk, _res);
493 if (err) {
494 BT_ERR("Encrypt error");
495 return err;
496 }
497
498 /* The output of the random address function ah is:
499 * ah(k, r) = e(k, r') mod 2^24
500 * The output of the security function e is then truncated to 24 bits
501 * by taking the least significant 24 bits of the output of e as the
502 * result of ah.
503 */
504 memcpy(res, _res, 3);
505
506 return 0;
507 }
508
509 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
510 const bdaddr_t *bdaddr)
511 {
512 struct l2cap_chan *chan = hdev->smp_data;
513 struct smp_dev *smp;
514 u8 hash[3];
515 int err;
516
517 if (!chan || !chan->data)
518 return false;
519
520 smp = chan->data;
521
522 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
523
524 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash);
525 if (err)
526 return false;
527
528 return !crypto_memneq(bdaddr->b, hash, 3);
529 }
530
531 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
532 {
533 struct l2cap_chan *chan = hdev->smp_data;
534 struct smp_dev *smp;
535 int err;
536
537 if (!chan || !chan->data)
538 return -EOPNOTSUPP;
539
540 smp = chan->data;
541
542 get_random_bytes(&rpa->b[3], 3);
543
544 rpa->b[5] &= 0x3f; /* Clear two most significant bits */
545 rpa->b[5] |= 0x40; /* Set second most significant bit */
546
547 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b);
548 if (err < 0)
549 return err;
550
551 BT_DBG("RPA %pMR", rpa);
552
553 return 0;
554 }
555
556 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
557 {
558 struct l2cap_chan *chan = hdev->smp_data;
559 struct smp_dev *smp;
560 int err;
561
562 if (!chan || !chan->data)
563 return -EOPNOTSUPP;
564
565 smp = chan->data;
566
567 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
568 BT_DBG("Using debug keys");
569 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk);
570 if (err)
571 return err;
572 memcpy(smp->local_pk, debug_pk, 64);
573 smp->debug_key = true;
574 } else {
575 while (true) {
576 /* Generate key pair for Secure Connections */
577 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk);
578 if (err)
579 return err;
580
581 /* This is unlikely, but we need to check that
582 * we didn't accidentially generate a debug key.
583 */
584 if (crypto_memneq(smp->local_pk, debug_pk, 64))
585 break;
586 }
587 smp->debug_key = false;
588 }
589
590 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
591 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
592
593 get_random_bytes(smp->local_rand, 16);
594
595 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk,
596 smp->local_rand, 0, hash);
597 if (err < 0)
598 return err;
599
600 memcpy(rand, smp->local_rand, 16);
601
602 return 0;
603 }
604
605 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
606 {
607 struct l2cap_chan *chan = conn->smp;
608 struct smp_chan *smp;
609 struct kvec iv[2];
610 struct msghdr msg;
611
612 if (!chan)
613 return;
614
615 BT_DBG("code 0x%2.2x", code);
616
617 iv[0].iov_base = &code;
618 iv[0].iov_len = 1;
619
620 iv[1].iov_base = data;
621 iv[1].iov_len = len;
622
623 memset(&msg, 0, sizeof(msg));
624
625 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
626
627 l2cap_chan_send(chan, &msg, 1 + len);
628
629 if (!chan->data)
630 return;
631
632 smp = chan->data;
633
634 cancel_delayed_work_sync(&smp->security_timer);
635 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
636 }
637
638 static u8 authreq_to_seclevel(u8 authreq)
639 {
640 if (authreq & SMP_AUTH_MITM) {
641 if (authreq & SMP_AUTH_SC)
642 return BT_SECURITY_FIPS;
643 else
644 return BT_SECURITY_HIGH;
645 } else {
646 return BT_SECURITY_MEDIUM;
647 }
648 }
649
650 static __u8 seclevel_to_authreq(__u8 sec_level)
651 {
652 switch (sec_level) {
653 case BT_SECURITY_FIPS:
654 case BT_SECURITY_HIGH:
655 return SMP_AUTH_MITM | SMP_AUTH_BONDING;
656 case BT_SECURITY_MEDIUM:
657 return SMP_AUTH_BONDING;
658 default:
659 return SMP_AUTH_NONE;
660 }
661 }
662
663 static void build_pairing_cmd(struct l2cap_conn *conn,
664 struct smp_cmd_pairing *req,
665 struct smp_cmd_pairing *rsp, __u8 authreq)
666 {
667 struct l2cap_chan *chan = conn->smp;
668 struct smp_chan *smp = chan->data;
669 struct hci_conn *hcon = conn->hcon;
670 struct hci_dev *hdev = hcon->hdev;
671 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
672
673 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
674 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
675 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
676 authreq |= SMP_AUTH_BONDING;
677 } else {
678 authreq &= ~SMP_AUTH_BONDING;
679 }
680
681 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
682 remote_dist |= SMP_DIST_ID_KEY;
683
684 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
685 local_dist |= SMP_DIST_ID_KEY;
686
687 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) &&
688 (authreq & SMP_AUTH_SC)) {
689 struct oob_data *oob_data;
690 u8 bdaddr_type;
691
692 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) {
693 local_dist |= SMP_DIST_LINK_KEY;
694 remote_dist |= SMP_DIST_LINK_KEY;
695 }
696
697 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
698 bdaddr_type = BDADDR_LE_PUBLIC;
699 else
700 bdaddr_type = BDADDR_LE_RANDOM;
701
702 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
703 bdaddr_type);
704 if (oob_data && oob_data->present) {
705 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags);
706 oob_flag = SMP_OOB_PRESENT;
707 memcpy(smp->rr, oob_data->rand256, 16);
708 memcpy(smp->pcnf, oob_data->hash256, 16);
709 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf);
710 SMP_DBG("OOB Remote Random: %16phN", smp->rr);
711 }
712
713 } else {
714 authreq &= ~SMP_AUTH_SC;
715 }
716
717 if (rsp == NULL) {
718 req->io_capability = conn->hcon->io_capability;
719 req->oob_flag = oob_flag;
720 req->max_key_size = SMP_DEV(hdev)->max_key_size;
721 req->init_key_dist = local_dist;
722 req->resp_key_dist = remote_dist;
723 req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
724
725 smp->remote_key_dist = remote_dist;
726 return;
727 }
728
729 rsp->io_capability = conn->hcon->io_capability;
730 rsp->oob_flag = oob_flag;
731 rsp->max_key_size = SMP_DEV(hdev)->max_key_size;
732 rsp->init_key_dist = req->init_key_dist & remote_dist;
733 rsp->resp_key_dist = req->resp_key_dist & local_dist;
734 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
735
736 smp->remote_key_dist = rsp->init_key_dist;
737 }
738
739 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
740 {
741 struct l2cap_chan *chan = conn->smp;
742 struct hci_dev *hdev = conn->hcon->hdev;
743 struct smp_chan *smp = chan->data;
744
745 if (max_key_size > SMP_DEV(hdev)->max_key_size ||
746 max_key_size < SMP_MIN_ENC_KEY_SIZE)
747 return SMP_ENC_KEY_SIZE;
748
749 smp->enc_key_size = max_key_size;
750
751 return 0;
752 }
753
754 static void smp_chan_destroy(struct l2cap_conn *conn)
755 {
756 struct l2cap_chan *chan = conn->smp;
757 struct smp_chan *smp = chan->data;
758 struct hci_conn *hcon = conn->hcon;
759 bool complete;
760
761 BUG_ON(!smp);
762
763 cancel_delayed_work_sync(&smp->security_timer);
764
765 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
766 mgmt_smp_complete(hcon, complete);
767
768 kzfree(smp->csrk);
769 kzfree(smp->slave_csrk);
770 kzfree(smp->link_key);
771
772 crypto_free_cipher(smp->tfm_aes);
773 crypto_free_shash(smp->tfm_cmac);
774 crypto_free_kpp(smp->tfm_ecdh);
775
776 /* Ensure that we don't leave any debug key around if debug key
777 * support hasn't been explicitly enabled.
778 */
779 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
780 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) {
781 list_del_rcu(&smp->ltk->list);
782 kfree_rcu(smp->ltk, rcu);
783 smp->ltk = NULL;
784 }
785
786 /* If pairing failed clean up any keys we might have */
787 if (!complete) {
788 if (smp->ltk) {
789 list_del_rcu(&smp->ltk->list);
790 kfree_rcu(smp->ltk, rcu);
791 }
792
793 if (smp->slave_ltk) {
794 list_del_rcu(&smp->slave_ltk->list);
795 kfree_rcu(smp->slave_ltk, rcu);
796 }
797
798 if (smp->remote_irk) {
799 list_del_rcu(&smp->remote_irk->list);
800 kfree_rcu(smp->remote_irk, rcu);
801 }
802 }
803
804 chan->data = NULL;
805 kzfree(smp);
806 hci_conn_drop(hcon);
807 }
808
809 static void smp_failure(struct l2cap_conn *conn, u8 reason)
810 {
811 struct hci_conn *hcon = conn->hcon;
812 struct l2cap_chan *chan = conn->smp;
813
814 if (reason)
815 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
816 &reason);
817
818 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE);
819
820 if (chan->data)
821 smp_chan_destroy(conn);
822 }
823
824 #define JUST_WORKS 0x00
825 #define JUST_CFM 0x01
826 #define REQ_PASSKEY 0x02
827 #define CFM_PASSKEY 0x03
828 #define REQ_OOB 0x04
829 #define DSP_PASSKEY 0x05
830 #define OVERLAP 0xFF
831
832 static const u8 gen_method[5][5] = {
833 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
834 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
835 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
836 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
837 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
838 };
839
840 static const u8 sc_method[5][5] = {
841 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
842 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
843 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
844 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
845 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
846 };
847
848 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
849 {
850 /* If either side has unknown io_caps, use JUST_CFM (which gets
851 * converted later to JUST_WORKS if we're initiators.
852 */
853 if (local_io > SMP_IO_KEYBOARD_DISPLAY ||
854 remote_io > SMP_IO_KEYBOARD_DISPLAY)
855 return JUST_CFM;
856
857 if (test_bit(SMP_FLAG_SC, &smp->flags))
858 return sc_method[remote_io][local_io];
859
860 return gen_method[remote_io][local_io];
861 }
862
863 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
864 u8 local_io, u8 remote_io)
865 {
866 struct hci_conn *hcon = conn->hcon;
867 struct l2cap_chan *chan = conn->smp;
868 struct smp_chan *smp = chan->data;
869 u32 passkey = 0;
870 int ret = 0;
871
872 /* Initialize key for JUST WORKS */
873 memset(smp->tk, 0, sizeof(smp->tk));
874 clear_bit(SMP_FLAG_TK_VALID, &smp->flags);
875
876 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io);
877
878 /* If neither side wants MITM, either "just" confirm an incoming
879 * request or use just-works for outgoing ones. The JUST_CFM
880 * will be converted to JUST_WORKS if necessary later in this
881 * function. If either side has MITM look up the method from the
882 * table.
883 */
884 if (!(auth & SMP_AUTH_MITM))
885 smp->method = JUST_CFM;
886 else
887 smp->method = get_auth_method(smp, local_io, remote_io);
888
889 /* Don't confirm locally initiated pairing attempts */
890 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
891 &smp->flags))
892 smp->method = JUST_WORKS;
893
894 /* Don't bother user space with no IO capabilities */
895 if (smp->method == JUST_CFM &&
896 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
897 smp->method = JUST_WORKS;
898
899 /* If Just Works, Continue with Zero TK */
900 if (smp->method == JUST_WORKS) {
901 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
902 return 0;
903 }
904
905 /* If this function is used for SC -> legacy fallback we
906 * can only recover the just-works case.
907 */
908 if (test_bit(SMP_FLAG_SC, &smp->flags))
909 return -EINVAL;
910
911 /* Not Just Works/Confirm results in MITM Authentication */
912 if (smp->method != JUST_CFM) {
913 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
914 if (hcon->pending_sec_level < BT_SECURITY_HIGH)
915 hcon->pending_sec_level = BT_SECURITY_HIGH;
916 }
917
918 /* If both devices have Keyoard-Display I/O, the master
919 * Confirms and the slave Enters the passkey.
920 */
921 if (smp->method == OVERLAP) {
922 if (hcon->role == HCI_ROLE_MASTER)
923 smp->method = CFM_PASSKEY;
924 else
925 smp->method = REQ_PASSKEY;
926 }
927
928 /* Generate random passkey. */
929 if (smp->method == CFM_PASSKEY) {
930 memset(smp->tk, 0, sizeof(smp->tk));
931 get_random_bytes(&passkey, sizeof(passkey));
932 passkey %= 1000000;
933 put_unaligned_le32(passkey, smp->tk);
934 BT_DBG("PassKey: %d", passkey);
935 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
936 }
937
938 if (smp->method == REQ_PASSKEY)
939 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
940 hcon->type, hcon->dst_type);
941 else if (smp->method == JUST_CFM)
942 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
943 hcon->type, hcon->dst_type,
944 passkey, 1);
945 else
946 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst,
947 hcon->type, hcon->dst_type,
948 passkey, 0);
949
950 return ret;
951 }
952
953 static u8 smp_confirm(struct smp_chan *smp)
954 {
955 struct l2cap_conn *conn = smp->conn;
956 struct smp_cmd_pairing_confirm cp;
957 int ret;
958
959 BT_DBG("conn %p", conn);
960
961 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
962 conn->hcon->init_addr_type, &conn->hcon->init_addr,
963 conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
964 cp.confirm_val);
965 if (ret)
966 return SMP_UNSPECIFIED;
967
968 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
969
970 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
971
972 if (conn->hcon->out)
973 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
974 else
975 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
976
977 return 0;
978 }
979
980 static u8 smp_random(struct smp_chan *smp)
981 {
982 struct l2cap_conn *conn = smp->conn;
983 struct hci_conn *hcon = conn->hcon;
984 u8 confirm[16];
985 int ret;
986
987 if (IS_ERR_OR_NULL(smp->tfm_aes))
988 return SMP_UNSPECIFIED;
989
990 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
991
992 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
993 hcon->init_addr_type, &hcon->init_addr,
994 hcon->resp_addr_type, &hcon->resp_addr, confirm);
995 if (ret)
996 return SMP_UNSPECIFIED;
997
998 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) {
999 bt_dev_err(hcon->hdev, "pairing failed "
1000 "(confirmation values mismatch)");
1001 return SMP_CONFIRM_FAILED;
1002 }
1003
1004 if (hcon->out) {
1005 u8 stk[16];
1006 __le64 rand = 0;
1007 __le16 ediv = 0;
1008
1009 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
1010
1011 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
1012 return SMP_UNSPECIFIED;
1013
1014 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size);
1015 hcon->enc_key_size = smp->enc_key_size;
1016 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
1017 } else {
1018 u8 stk[16], auth;
1019 __le64 rand = 0;
1020 __le16 ediv = 0;
1021
1022 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
1023 smp->prnd);
1024
1025 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
1026
1027 if (hcon->pending_sec_level == BT_SECURITY_HIGH)
1028 auth = 1;
1029 else
1030 auth = 0;
1031
1032 /* Even though there's no _SLAVE suffix this is the
1033 * slave STK we're adding for later lookup (the master
1034 * STK never needs to be stored).
1035 */
1036 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1037 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand);
1038 }
1039
1040 return 0;
1041 }
1042
1043 static void smp_notify_keys(struct l2cap_conn *conn)
1044 {
1045 struct l2cap_chan *chan = conn->smp;
1046 struct smp_chan *smp = chan->data;
1047 struct hci_conn *hcon = conn->hcon;
1048 struct hci_dev *hdev = hcon->hdev;
1049 struct smp_cmd_pairing *req = (void *) &smp->preq[1];
1050 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1];
1051 bool persistent;
1052
1053 if (hcon->type == ACL_LINK) {
1054 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
1055 persistent = false;
1056 else
1057 persistent = !test_bit(HCI_CONN_FLUSH_KEY,
1058 &hcon->flags);
1059 } else {
1060 /* The LTKs, IRKs and CSRKs should be persistent only if
1061 * both sides had the bonding bit set in their
1062 * authentication requests.
1063 */
1064 persistent = !!((req->auth_req & rsp->auth_req) &
1065 SMP_AUTH_BONDING);
1066 }
1067
1068 if (smp->remote_irk) {
1069 mgmt_new_irk(hdev, smp->remote_irk, persistent);
1070
1071 /* Now that user space can be considered to know the
1072 * identity address track the connection based on it
1073 * from now on (assuming this is an LE link).
1074 */
1075 if (hcon->type == LE_LINK) {
1076 bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
1077 hcon->dst_type = smp->remote_irk->addr_type;
1078 queue_work(hdev->workqueue, &conn->id_addr_update_work);
1079 }
1080 }
1081
1082 if (smp->csrk) {
1083 smp->csrk->bdaddr_type = hcon->dst_type;
1084 bacpy(&smp->csrk->bdaddr, &hcon->dst);
1085 mgmt_new_csrk(hdev, smp->csrk, persistent);
1086 }
1087
1088 if (smp->slave_csrk) {
1089 smp->slave_csrk->bdaddr_type = hcon->dst_type;
1090 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst);
1091 mgmt_new_csrk(hdev, smp->slave_csrk, persistent);
1092 }
1093
1094 if (smp->ltk) {
1095 smp->ltk->bdaddr_type = hcon->dst_type;
1096 bacpy(&smp->ltk->bdaddr, &hcon->dst);
1097 mgmt_new_ltk(hdev, smp->ltk, persistent);
1098 }
1099
1100 if (smp->slave_ltk) {
1101 smp->slave_ltk->bdaddr_type = hcon->dst_type;
1102 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
1103 mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
1104 }
1105
1106 if (smp->link_key) {
1107 struct link_key *key;
1108 u8 type;
1109
1110 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1111 type = HCI_LK_DEBUG_COMBINATION;
1112 else if (hcon->sec_level == BT_SECURITY_FIPS)
1113 type = HCI_LK_AUTH_COMBINATION_P256;
1114 else
1115 type = HCI_LK_UNAUTH_COMBINATION_P256;
1116
1117 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
1118 smp->link_key, type, 0, &persistent);
1119 if (key) {
1120 mgmt_new_link_key(hdev, key, persistent);
1121
1122 /* Don't keep debug keys around if the relevant
1123 * flag is not set.
1124 */
1125 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) &&
1126 key->type == HCI_LK_DEBUG_COMBINATION) {
1127 list_del_rcu(&key->list);
1128 kfree_rcu(key, rcu);
1129 }
1130 }
1131 }
1132 }
1133
1134 static void sc_add_ltk(struct smp_chan *smp)
1135 {
1136 struct hci_conn *hcon = smp->conn->hcon;
1137 u8 key_type, auth;
1138
1139 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
1140 key_type = SMP_LTK_P256_DEBUG;
1141 else
1142 key_type = SMP_LTK_P256;
1143
1144 if (hcon->pending_sec_level == BT_SECURITY_FIPS)
1145 auth = 1;
1146 else
1147 auth = 0;
1148
1149 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
1150 key_type, auth, smp->tk, smp->enc_key_size,
1151 0, 0);
1152 }
1153
1154 static void sc_generate_link_key(struct smp_chan *smp)
1155 {
1156 /* From core spec. Spells out in ASCII as 'lebr'. */
1157 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
1158
1159 smp->link_key = kzalloc(16, GFP_KERNEL);
1160 if (!smp->link_key)
1161 return;
1162
1163 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1164 /* SALT = 0x00000000000000000000000000000000746D7031 */
1165 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 };
1166
1167 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) {
1168 kzfree(smp->link_key);
1169 smp->link_key = NULL;
1170 return;
1171 }
1172 } else {
1173 /* From core spec. Spells out in ASCII as 'tmp1'. */
1174 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
1175
1176 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
1177 kzfree(smp->link_key);
1178 smp->link_key = NULL;
1179 return;
1180 }
1181 }
1182
1183 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
1184 kzfree(smp->link_key);
1185 smp->link_key = NULL;
1186 return;
1187 }
1188 }
1189
1190 static void smp_allow_key_dist(struct smp_chan *smp)
1191 {
1192 /* Allow the first expected phase 3 PDU. The rest of the PDUs
1193 * will be allowed in each PDU handler to ensure we receive
1194 * them in the correct order.
1195 */
1196 if (smp->remote_key_dist & SMP_DIST_ENC_KEY)
1197 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO);
1198 else if (smp->remote_key_dist & SMP_DIST_ID_KEY)
1199 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
1200 else if (smp->remote_key_dist & SMP_DIST_SIGN)
1201 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
1202 }
1203
1204 static void sc_generate_ltk(struct smp_chan *smp)
1205 {
1206 /* From core spec. Spells out in ASCII as 'brle'. */
1207 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
1208 struct hci_conn *hcon = smp->conn->hcon;
1209 struct hci_dev *hdev = hcon->hdev;
1210 struct link_key *key;
1211
1212 key = hci_find_link_key(hdev, &hcon->dst);
1213 if (!key) {
1214 bt_dev_err(hdev, "no Link Key found to generate LTK");
1215 return;
1216 }
1217
1218 if (key->type == HCI_LK_DEBUG_COMBINATION)
1219 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1220
1221 if (test_bit(SMP_FLAG_CT2, &smp->flags)) {
1222 /* SALT = 0x00000000000000000000000000000000746D7032 */
1223 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 };
1224
1225 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk))
1226 return;
1227 } else {
1228 /* From core spec. Spells out in ASCII as 'tmp2'. */
1229 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
1230
1231 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
1232 return;
1233 }
1234
1235 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
1236 return;
1237
1238 sc_add_ltk(smp);
1239 }
1240
1241 static void smp_distribute_keys(struct smp_chan *smp)
1242 {
1243 struct smp_cmd_pairing *req, *rsp;
1244 struct l2cap_conn *conn = smp->conn;
1245 struct hci_conn *hcon = conn->hcon;
1246 struct hci_dev *hdev = hcon->hdev;
1247 __u8 *keydist;
1248
1249 BT_DBG("conn %p", conn);
1250
1251 rsp = (void *) &smp->prsp[1];
1252
1253 /* The responder sends its keys first */
1254 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) {
1255 smp_allow_key_dist(smp);
1256 return;
1257 }
1258
1259 req = (void *) &smp->preq[1];
1260
1261 if (hcon->out) {
1262 keydist = &rsp->init_key_dist;
1263 *keydist &= req->init_key_dist;
1264 } else {
1265 keydist = &rsp->resp_key_dist;
1266 *keydist &= req->resp_key_dist;
1267 }
1268
1269 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1270 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
1271 sc_generate_link_key(smp);
1272 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
1273 sc_generate_ltk(smp);
1274
1275 /* Clear the keys which are generated but not distributed */
1276 *keydist &= ~SMP_SC_NO_DIST;
1277 }
1278
1279 BT_DBG("keydist 0x%x", *keydist);
1280
1281 if (*keydist & SMP_DIST_ENC_KEY) {
1282 struct smp_cmd_encrypt_info enc;
1283 struct smp_cmd_master_ident ident;
1284 struct smp_ltk *ltk;
1285 u8 authenticated;
1286 __le16 ediv;
1287 __le64 rand;
1288
1289 /* Make sure we generate only the significant amount of
1290 * bytes based on the encryption key size, and set the rest
1291 * of the value to zeroes.
1292 */
1293 get_random_bytes(enc.ltk, smp->enc_key_size);
1294 memset(enc.ltk + smp->enc_key_size, 0,
1295 sizeof(enc.ltk) - smp->enc_key_size);
1296
1297 get_random_bytes(&ediv, sizeof(ediv));
1298 get_random_bytes(&rand, sizeof(rand));
1299
1300 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
1301
1302 authenticated = hcon->sec_level == BT_SECURITY_HIGH;
1303 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type,
1304 SMP_LTK_SLAVE, authenticated, enc.ltk,
1305 smp->enc_key_size, ediv, rand);
1306 smp->slave_ltk = ltk;
1307
1308 ident.ediv = ediv;
1309 ident.rand = rand;
1310
1311 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
1312
1313 *keydist &= ~SMP_DIST_ENC_KEY;
1314 }
1315
1316 if (*keydist & SMP_DIST_ID_KEY) {
1317 struct smp_cmd_ident_addr_info addrinfo;
1318 struct smp_cmd_ident_info idinfo;
1319
1320 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk));
1321
1322 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
1323
1324 /* The hci_conn contains the local identity address
1325 * after the connection has been established.
1326 *
1327 * This is true even when the connection has been
1328 * established using a resolvable random address.
1329 */
1330 bacpy(&addrinfo.bdaddr, &hcon->src);
1331 addrinfo.addr_type = hcon->src_type;
1332
1333 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
1334 &addrinfo);
1335
1336 *keydist &= ~SMP_DIST_ID_KEY;
1337 }
1338
1339 if (*keydist & SMP_DIST_SIGN) {
1340 struct smp_cmd_sign_info sign;
1341 struct smp_csrk *csrk;
1342
1343 /* Generate a new random key */
1344 get_random_bytes(sign.csrk, sizeof(sign.csrk));
1345
1346 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
1347 if (csrk) {
1348 if (hcon->sec_level > BT_SECURITY_MEDIUM)
1349 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED;
1350 else
1351 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED;
1352 memcpy(csrk->val, sign.csrk, sizeof(csrk->val));
1353 }
1354 smp->slave_csrk = csrk;
1355
1356 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
1357
1358 *keydist &= ~SMP_DIST_SIGN;
1359 }
1360
1361 /* If there are still keys to be received wait for them */
1362 if (smp->remote_key_dist & KEY_DIST_MASK) {
1363 smp_allow_key_dist(smp);
1364 return;
1365 }
1366
1367 set_bit(SMP_FLAG_COMPLETE, &smp->flags);
1368 smp_notify_keys(conn);
1369
1370 smp_chan_destroy(conn);
1371 }
1372
1373 static void smp_timeout(struct work_struct *work)
1374 {
1375 struct smp_chan *smp = container_of(work, struct smp_chan,
1376 security_timer.work);
1377 struct l2cap_conn *conn = smp->conn;
1378
1379 BT_DBG("conn %p", conn);
1380
1381 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM);
1382 }
1383
1384 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
1385 {
1386 struct l2cap_chan *chan = conn->smp;
1387 struct smp_chan *smp;
1388
1389 smp = kzalloc(sizeof(*smp), GFP_ATOMIC);
1390 if (!smp)
1391 return NULL;
1392
1393 smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
1394 if (IS_ERR(smp->tfm_aes)) {
1395 BT_ERR("Unable to create AES crypto context");
1396 goto zfree_smp;
1397 }
1398
1399 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
1400 if (IS_ERR(smp->tfm_cmac)) {
1401 BT_ERR("Unable to create CMAC crypto context");
1402 goto free_cipher;
1403 }
1404
1405 smp->tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0);
1406 if (IS_ERR(smp->tfm_ecdh)) {
1407 BT_ERR("Unable to create ECDH crypto context");
1408 goto free_shash;
1409 }
1410
1411 smp->conn = conn;
1412 chan->data = smp;
1413
1414 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL);
1415
1416 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
1417
1418 hci_conn_hold(conn->hcon);
1419
1420 return smp;
1421
1422 free_shash:
1423 crypto_free_shash(smp->tfm_cmac);
1424 free_cipher:
1425 crypto_free_cipher(smp->tfm_aes);
1426 zfree_smp:
1427 kzfree(smp);
1428 return NULL;
1429 }
1430
1431 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
1432 {
1433 struct hci_conn *hcon = smp->conn->hcon;
1434 u8 *na, *nb, a[7], b[7];
1435
1436 if (hcon->out) {
1437 na = smp->prnd;
1438 nb = smp->rrnd;
1439 } else {
1440 na = smp->rrnd;
1441 nb = smp->prnd;
1442 }
1443
1444 memcpy(a, &hcon->init_addr, 6);
1445 memcpy(b, &hcon->resp_addr, 6);
1446 a[6] = hcon->init_addr_type;
1447 b[6] = hcon->resp_addr_type;
1448
1449 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
1450 }
1451
1452 static void sc_dhkey_check(struct smp_chan *smp)
1453 {
1454 struct hci_conn *hcon = smp->conn->hcon;
1455 struct smp_cmd_dhkey_check check;
1456 u8 a[7], b[7], *local_addr, *remote_addr;
1457 u8 io_cap[3], r[16];
1458
1459 memcpy(a, &hcon->init_addr, 6);
1460 memcpy(b, &hcon->resp_addr, 6);
1461 a[6] = hcon->init_addr_type;
1462 b[6] = hcon->resp_addr_type;
1463
1464 if (hcon->out) {
1465 local_addr = a;
1466 remote_addr = b;
1467 memcpy(io_cap, &smp->preq[1], 3);
1468 } else {
1469 local_addr = b;
1470 remote_addr = a;
1471 memcpy(io_cap, &smp->prsp[1], 3);
1472 }
1473
1474 memset(r, 0, sizeof(r));
1475
1476 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
1477 put_unaligned_le32(hcon->passkey_notify, r);
1478
1479 if (smp->method == REQ_OOB)
1480 memcpy(r, smp->rr, 16);
1481
1482 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
1483 local_addr, remote_addr, check.e);
1484
1485 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
1486 }
1487
1488 static u8 sc_passkey_send_confirm(struct smp_chan *smp)
1489 {
1490 struct l2cap_conn *conn = smp->conn;
1491 struct hci_conn *hcon = conn->hcon;
1492 struct smp_cmd_pairing_confirm cfm;
1493 u8 r;
1494
1495 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1496 r |= 0x80;
1497
1498 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1499
1500 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
1501 cfm.confirm_val))
1502 return SMP_UNSPECIFIED;
1503
1504 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
1505
1506 return 0;
1507 }
1508
1509 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
1510 {
1511 struct l2cap_conn *conn = smp->conn;
1512 struct hci_conn *hcon = conn->hcon;
1513 struct hci_dev *hdev = hcon->hdev;
1514 u8 cfm[16], r;
1515
1516 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
1517 if (smp->passkey_round >= 20)
1518 return 0;
1519
1520 switch (smp_op) {
1521 case SMP_CMD_PAIRING_RANDOM:
1522 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
1523 r |= 0x80;
1524
1525 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
1526 smp->rrnd, r, cfm))
1527 return SMP_UNSPECIFIED;
1528
1529 if (crypto_memneq(smp->pcnf, cfm, 16))
1530 return SMP_CONFIRM_FAILED;
1531
1532 smp->passkey_round++;
1533
1534 if (smp->passkey_round == 20) {
1535 /* Generate MacKey and LTK */
1536 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
1537 return SMP_UNSPECIFIED;
1538 }
1539
1540 /* The round is only complete when the initiator
1541 * receives pairing random.
1542 */
1543 if (!hcon->out) {
1544 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1545 sizeof(smp->prnd), smp->prnd);
1546 if (smp->passkey_round == 20)
1547 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1548 else
1549 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1550 return 0;
1551 }
1552
1553 /* Start the next round */
1554 if (smp->passkey_round != 20)
1555 return sc_passkey_round(smp, 0);
1556
1557 /* Passkey rounds are complete - start DHKey Check */
1558 sc_dhkey_check(smp);
1559 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1560
1561 break;
1562
1563 case SMP_CMD_PAIRING_CONFIRM:
1564 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
1565 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
1566 return 0;
1567 }
1568
1569 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
1570
1571 if (hcon->out) {
1572 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
1573 sizeof(smp->prnd), smp->prnd);
1574 return 0;
1575 }
1576
1577 return sc_passkey_send_confirm(smp);
1578
1579 case SMP_CMD_PUBLIC_KEY:
1580 default:
1581 /* Initiating device starts the round */
1582 if (!hcon->out)
1583 return 0;
1584
1585 BT_DBG("%s Starting passkey round %u", hdev->name,
1586 smp->passkey_round + 1);
1587
1588 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1589
1590 return sc_passkey_send_confirm(smp);
1591 }
1592
1593 return 0;
1594 }
1595
1596 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
1597 {
1598 struct l2cap_conn *conn = smp->conn;
1599 struct hci_conn *hcon = conn->hcon;
1600 u8 smp_op;
1601
1602 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
1603
1604 switch (mgmt_op) {
1605 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1606 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
1607 return 0;
1608 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1609 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
1610 return 0;
1611 case MGMT_OP_USER_PASSKEY_REPLY:
1612 hcon->passkey_notify = le32_to_cpu(passkey);
1613 smp->passkey_round = 0;
1614
1615 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
1616 smp_op = SMP_CMD_PAIRING_CONFIRM;
1617 else
1618 smp_op = 0;
1619
1620 if (sc_passkey_round(smp, smp_op))
1621 return -EIO;
1622
1623 return 0;
1624 }
1625
1626 /* Initiator sends DHKey check first */
1627 if (hcon->out) {
1628 sc_dhkey_check(smp);
1629 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
1630 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
1631 sc_dhkey_check(smp);
1632 sc_add_ltk(smp);
1633 }
1634
1635 return 0;
1636 }
1637
1638 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
1639 {
1640 struct l2cap_conn *conn = hcon->l2cap_data;
1641 struct l2cap_chan *chan;
1642 struct smp_chan *smp;
1643 u32 value;
1644 int err;
1645
1646 BT_DBG("");
1647
1648 if (!conn)
1649 return -ENOTCONN;
1650
1651 chan = conn->smp;
1652 if (!chan)
1653 return -ENOTCONN;
1654
1655 l2cap_chan_lock(chan);
1656 if (!chan->data) {
1657 err = -ENOTCONN;
1658 goto unlock;
1659 }
1660
1661 smp = chan->data;
1662
1663 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1664 err = sc_user_reply(smp, mgmt_op, passkey);
1665 goto unlock;
1666 }
1667
1668 switch (mgmt_op) {
1669 case MGMT_OP_USER_PASSKEY_REPLY:
1670 value = le32_to_cpu(passkey);
1671 memset(smp->tk, 0, sizeof(smp->tk));
1672 BT_DBG("PassKey: %d", value);
1673 put_unaligned_le32(value, smp->tk);
1674 /* Fall Through */
1675 case MGMT_OP_USER_CONFIRM_REPLY:
1676 set_bit(SMP_FLAG_TK_VALID, &smp->flags);
1677 break;
1678 case MGMT_OP_USER_PASSKEY_NEG_REPLY:
1679 case MGMT_OP_USER_CONFIRM_NEG_REPLY:
1680 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1681 err = 0;
1682 goto unlock;
1683 default:
1684 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED);
1685 err = -EOPNOTSUPP;
1686 goto unlock;
1687 }
1688
1689 err = 0;
1690
1691 /* If it is our turn to send Pairing Confirm, do so now */
1692 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) {
1693 u8 rsp = smp_confirm(smp);
1694 if (rsp)
1695 smp_failure(conn, rsp);
1696 }
1697
1698 unlock:
1699 l2cap_chan_unlock(chan);
1700 return err;
1701 }
1702
1703 static void build_bredr_pairing_cmd(struct smp_chan *smp,
1704 struct smp_cmd_pairing *req,
1705 struct smp_cmd_pairing *rsp)
1706 {
1707 struct l2cap_conn *conn = smp->conn;
1708 struct hci_dev *hdev = conn->hcon->hdev;
1709 u8 local_dist = 0, remote_dist = 0;
1710
1711 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) {
1712 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1713 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
1714 }
1715
1716 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING))
1717 remote_dist |= SMP_DIST_ID_KEY;
1718
1719 if (hci_dev_test_flag(hdev, HCI_PRIVACY))
1720 local_dist |= SMP_DIST_ID_KEY;
1721
1722 if (!rsp) {
1723 memset(req, 0, sizeof(*req));
1724
1725 req->auth_req = SMP_AUTH_CT2;
1726 req->init_key_dist = local_dist;
1727 req->resp_key_dist = remote_dist;
1728 req->max_key_size = conn->hcon->enc_key_size;
1729
1730 smp->remote_key_dist = remote_dist;
1731
1732 return;
1733 }
1734
1735 memset(rsp, 0, sizeof(*rsp));
1736
1737 rsp->auth_req = SMP_AUTH_CT2;
1738 rsp->max_key_size = conn->hcon->enc_key_size;
1739 rsp->init_key_dist = req->init_key_dist & remote_dist;
1740 rsp->resp_key_dist = req->resp_key_dist & local_dist;
1741
1742 smp->remote_key_dist = rsp->init_key_dist;
1743 }
1744
1745 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
1746 {
1747 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
1748 struct l2cap_chan *chan = conn->smp;
1749 struct hci_dev *hdev = conn->hcon->hdev;
1750 struct smp_chan *smp;
1751 u8 key_size, auth, sec_level;
1752 int ret;
1753
1754 BT_DBG("conn %p", conn);
1755
1756 if (skb->len < sizeof(*req))
1757 return SMP_INVALID_PARAMS;
1758
1759 if (conn->hcon->role != HCI_ROLE_SLAVE)
1760 return SMP_CMD_NOTSUPP;
1761
1762 if (!chan->data)
1763 smp = smp_chan_create(conn);
1764 else
1765 smp = chan->data;
1766
1767 if (!smp)
1768 return SMP_UNSPECIFIED;
1769
1770 /* We didn't start the pairing, so match remote */
1771 auth = req->auth_req & AUTH_REQ_MASK(hdev);
1772
1773 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
1774 (auth & SMP_AUTH_BONDING))
1775 return SMP_PAIRING_NOTSUPP;
1776
1777 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1778 return SMP_AUTH_REQUIREMENTS;
1779
1780 smp->preq[0] = SMP_CMD_PAIRING_REQ;
1781 memcpy(&smp->preq[1], req, sizeof(*req));
1782 skb_pull(skb, sizeof(*req));
1783
1784 /* If the remote side's OOB flag is set it means it has
1785 * successfully received our local OOB data - therefore set the
1786 * flag to indicate that local OOB is in use.
1787 */
1788 if (req->oob_flag == SMP_OOB_PRESENT)
1789 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1790
1791 /* SMP over BR/EDR requires special treatment */
1792 if (conn->hcon->type == ACL_LINK) {
1793 /* We must have a BR/EDR SC link */
1794 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) &&
1795 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
1796 return SMP_CROSS_TRANSP_NOT_ALLOWED;
1797
1798 set_bit(SMP_FLAG_SC, &smp->flags);
1799
1800 build_bredr_pairing_cmd(smp, req, &rsp);
1801
1802 if (req->auth_req & SMP_AUTH_CT2)
1803 set_bit(SMP_FLAG_CT2, &smp->flags);
1804
1805 key_size = min(req->max_key_size, rsp.max_key_size);
1806 if (check_enc_key_size(conn, key_size))
1807 return SMP_ENC_KEY_SIZE;
1808
1809 /* Clear bits which are generated but not distributed */
1810 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1811
1812 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1813 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1814 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1815
1816 smp_distribute_keys(smp);
1817 return 0;
1818 }
1819
1820 build_pairing_cmd(conn, req, &rsp, auth);
1821
1822 if (rsp.auth_req & SMP_AUTH_SC) {
1823 set_bit(SMP_FLAG_SC, &smp->flags);
1824
1825 if (rsp.auth_req & SMP_AUTH_CT2)
1826 set_bit(SMP_FLAG_CT2, &smp->flags);
1827 }
1828
1829 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
1830 sec_level = BT_SECURITY_MEDIUM;
1831 else
1832 sec_level = authreq_to_seclevel(auth);
1833
1834 if (sec_level > conn->hcon->pending_sec_level)
1835 conn->hcon->pending_sec_level = sec_level;
1836
1837 /* If we need MITM check that it can be achieved */
1838 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1839 u8 method;
1840
1841 method = get_auth_method(smp, conn->hcon->io_capability,
1842 req->io_capability);
1843 if (method == JUST_WORKS || method == JUST_CFM)
1844 return SMP_AUTH_REQUIREMENTS;
1845 }
1846
1847 key_size = min(req->max_key_size, rsp.max_key_size);
1848 if (check_enc_key_size(conn, key_size))
1849 return SMP_ENC_KEY_SIZE;
1850
1851 get_random_bytes(smp->prnd, sizeof(smp->prnd));
1852
1853 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1854 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
1855
1856 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
1857
1858 clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
1859
1860 /* Strictly speaking we shouldn't allow Pairing Confirm for the
1861 * SC case, however some implementations incorrectly copy RFU auth
1862 * req bits from our security request, which may create a false
1863 * positive SC enablement.
1864 */
1865 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
1866
1867 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
1868 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
1869 /* Clear bits which are generated but not distributed */
1870 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1871 /* Wait for Public Key from Initiating Device */
1872 return 0;
1873 }
1874
1875 /* Request setup of TK */
1876 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
1877 if (ret)
1878 return SMP_UNSPECIFIED;
1879
1880 return 0;
1881 }
1882
1883 static u8 sc_send_public_key(struct smp_chan *smp)
1884 {
1885 struct hci_dev *hdev = smp->conn->hcon->hdev;
1886
1887 BT_DBG("");
1888
1889 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
1890 struct l2cap_chan *chan = hdev->smp_data;
1891 struct smp_dev *smp_dev;
1892
1893 if (!chan || !chan->data)
1894 return SMP_UNSPECIFIED;
1895
1896 smp_dev = chan->data;
1897
1898 memcpy(smp->local_pk, smp_dev->local_pk, 64);
1899 memcpy(smp->lr, smp_dev->local_rand, 16);
1900
1901 if (smp_dev->debug_key)
1902 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1903
1904 goto done;
1905 }
1906
1907 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
1908 BT_DBG("Using debug keys");
1909 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk))
1910 return SMP_UNSPECIFIED;
1911 memcpy(smp->local_pk, debug_pk, 64);
1912 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
1913 } else {
1914 while (true) {
1915 /* Generate key pair for Secure Connections */
1916 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk))
1917 return SMP_UNSPECIFIED;
1918
1919 /* This is unlikely, but we need to check that
1920 * we didn't accidentially generate a debug key.
1921 */
1922 if (crypto_memneq(smp->local_pk, debug_pk, 64))
1923 break;
1924 }
1925 }
1926
1927 done:
1928 SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
1929 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32);
1930
1931 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
1932
1933 return 0;
1934 }
1935
1936 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
1937 {
1938 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
1939 struct l2cap_chan *chan = conn->smp;
1940 struct smp_chan *smp = chan->data;
1941 struct hci_dev *hdev = conn->hcon->hdev;
1942 u8 key_size, auth;
1943 int ret;
1944
1945 BT_DBG("conn %p", conn);
1946
1947 if (skb->len < sizeof(*rsp))
1948 return SMP_INVALID_PARAMS;
1949
1950 if (conn->hcon->role != HCI_ROLE_MASTER)
1951 return SMP_CMD_NOTSUPP;
1952
1953 skb_pull(skb, sizeof(*rsp));
1954
1955 req = (void *) &smp->preq[1];
1956
1957 key_size = min(req->max_key_size, rsp->max_key_size);
1958 if (check_enc_key_size(conn, key_size))
1959 return SMP_ENC_KEY_SIZE;
1960
1961 auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
1962
1963 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
1964 return SMP_AUTH_REQUIREMENTS;
1965
1966 /* If the remote side's OOB flag is set it means it has
1967 * successfully received our local OOB data - therefore set the
1968 * flag to indicate that local OOB is in use.
1969 */
1970 if (rsp->oob_flag == SMP_OOB_PRESENT)
1971 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags);
1972
1973 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
1974 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
1975
1976 /* Update remote key distribution in case the remote cleared
1977 * some bits that we had enabled in our request.
1978 */
1979 smp->remote_key_dist &= rsp->resp_key_dist;
1980
1981 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2))
1982 set_bit(SMP_FLAG_CT2, &smp->flags);
1983
1984 /* For BR/EDR this means we're done and can start phase 3 */
1985 if (conn->hcon->type == ACL_LINK) {
1986 /* Clear bits which are generated but not distributed */
1987 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
1988 smp_distribute_keys(smp);
1989 return 0;
1990 }
1991
1992 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
1993 set_bit(SMP_FLAG_SC, &smp->flags);
1994 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
1995 conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
1996
1997 /* If we need MITM check that it can be achieved */
1998 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
1999 u8 method;
2000
2001 method = get_auth_method(smp, req->io_capability,
2002 rsp->io_capability);
2003 if (method == JUST_WORKS || method == JUST_CFM)
2004 return SMP_AUTH_REQUIREMENTS;
2005 }
2006
2007 get_random_bytes(smp->prnd, sizeof(smp->prnd));
2008
2009 /* Update remote key distribution in case the remote cleared
2010 * some bits that we had enabled in our request.
2011 */
2012 smp->remote_key_dist &= rsp->resp_key_dist;
2013
2014 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2015 /* Clear bits which are generated but not distributed */
2016 smp->remote_key_dist &= ~SMP_SC_NO_DIST;
2017 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
2018 return sc_send_public_key(smp);
2019 }
2020
2021 auth |= req->auth_req;
2022
2023 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
2024 if (ret)
2025 return SMP_UNSPECIFIED;
2026
2027 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2028
2029 /* Can't compose response until we have been confirmed */
2030 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2031 return smp_confirm(smp);
2032
2033 return 0;
2034 }
2035
2036 static u8 sc_check_confirm(struct smp_chan *smp)
2037 {
2038 struct l2cap_conn *conn = smp->conn;
2039
2040 BT_DBG("");
2041
2042 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2043 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
2044
2045 if (conn->hcon->out) {
2046 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2047 smp->prnd);
2048 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2049 }
2050
2051 return 0;
2052 }
2053
2054 /* Work-around for some implementations that incorrectly copy RFU bits
2055 * from our security request and thereby create the impression that
2056 * we're doing SC when in fact the remote doesn't support it.
2057 */
2058 static int fixup_sc_false_positive(struct smp_chan *smp)
2059 {
2060 struct l2cap_conn *conn = smp->conn;
2061 struct hci_conn *hcon = conn->hcon;
2062 struct hci_dev *hdev = hcon->hdev;
2063 struct smp_cmd_pairing *req, *rsp;
2064 u8 auth;
2065
2066 /* The issue is only observed when we're in slave role */
2067 if (hcon->out)
2068 return SMP_UNSPECIFIED;
2069
2070 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) {
2071 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode");
2072 return SMP_UNSPECIFIED;
2073 }
2074
2075 bt_dev_err(hdev, "trying to fall back to legacy SMP");
2076
2077 req = (void *) &smp->preq[1];
2078 rsp = (void *) &smp->prsp[1];
2079
2080 /* Rebuild key dist flags which may have been cleared for SC */
2081 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist);
2082
2083 auth = req->auth_req & AUTH_REQ_MASK(hdev);
2084
2085 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) {
2086 bt_dev_err(hdev, "failed to fall back to legacy SMP");
2087 return SMP_UNSPECIFIED;
2088 }
2089
2090 clear_bit(SMP_FLAG_SC, &smp->flags);
2091
2092 return 0;
2093 }
2094
2095 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
2096 {
2097 struct l2cap_chan *chan = conn->smp;
2098 struct smp_chan *smp = chan->data;
2099
2100 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
2101
2102 if (skb->len < sizeof(smp->pcnf))
2103 return SMP_INVALID_PARAMS;
2104
2105 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
2106 skb_pull(skb, sizeof(smp->pcnf));
2107
2108 if (test_bit(SMP_FLAG_SC, &smp->flags)) {
2109 int ret;
2110
2111 /* Public Key exchange must happen before any other steps */
2112 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
2113 return sc_check_confirm(smp);
2114
2115 BT_ERR("Unexpected SMP Pairing Confirm");
2116
2117 ret = fixup_sc_false_positive(smp);
2118 if (ret)
2119 return ret;
2120 }
2121
2122 if (conn->hcon->out) {
2123 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2124 smp->prnd);
2125 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2126 return 0;
2127 }
2128
2129 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags))
2130 return smp_confirm(smp);
2131
2132 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
2133
2134 return 0;
2135 }
2136
2137 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
2138 {
2139 struct l2cap_chan *chan = conn->smp;
2140 struct smp_chan *smp = chan->data;
2141 struct hci_conn *hcon = conn->hcon;
2142 u8 *pkax, *pkbx, *na, *nb;
2143 u32 passkey;
2144 int err;
2145
2146 BT_DBG("conn %p", conn);
2147
2148 if (skb->len < sizeof(smp->rrnd))
2149 return SMP_INVALID_PARAMS;
2150
2151 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
2152 skb_pull(skb, sizeof(smp->rrnd));
2153
2154 if (!test_bit(SMP_FLAG_SC, &smp->flags))
2155 return smp_random(smp);
2156
2157 if (hcon->out) {
2158 pkax = smp->local_pk;
2159 pkbx = smp->remote_pk;
2160 na = smp->prnd;
2161 nb = smp->rrnd;
2162 } else {
2163 pkax = smp->remote_pk;
2164 pkbx = smp->local_pk;
2165 na = smp->rrnd;
2166 nb = smp->prnd;
2167 }
2168
2169 if (smp->method == REQ_OOB) {
2170 if (!hcon->out)
2171 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2172 sizeof(smp->prnd), smp->prnd);
2173 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2174 goto mackey_and_ltk;
2175 }
2176
2177 /* Passkey entry has special treatment */
2178 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2179 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
2180
2181 if (hcon->out) {
2182 u8 cfm[16];
2183
2184 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
2185 smp->rrnd, 0, cfm);
2186 if (err)
2187 return SMP_UNSPECIFIED;
2188
2189 if (crypto_memneq(smp->pcnf, cfm, 16))
2190 return SMP_CONFIRM_FAILED;
2191 } else {
2192 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
2193 smp->prnd);
2194 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2195 }
2196
2197 mackey_and_ltk:
2198 /* Generate MacKey and LTK */
2199 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
2200 if (err)
2201 return SMP_UNSPECIFIED;
2202
2203 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
2204 if (hcon->out) {
2205 sc_dhkey_check(smp);
2206 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
2207 }
2208 return 0;
2209 }
2210
2211 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
2212 if (err)
2213 return SMP_UNSPECIFIED;
2214
2215 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
2216 hcon->dst_type, passkey, 0);
2217 if (err)
2218 return SMP_UNSPECIFIED;
2219
2220 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2221
2222 return 0;
2223 }
2224
2225 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
2226 {
2227 struct smp_ltk *key;
2228 struct hci_conn *hcon = conn->hcon;
2229
2230 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
2231 if (!key)
2232 return false;
2233
2234 if (smp_ltk_sec_level(key) < sec_level)
2235 return false;
2236
2237 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags))
2238 return true;
2239
2240 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size);
2241 hcon->enc_key_size = key->enc_size;
2242
2243 /* We never store STKs for master role, so clear this flag */
2244 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags);
2245
2246 return true;
2247 }
2248
2249 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
2250 enum smp_key_pref key_pref)
2251 {
2252 if (sec_level == BT_SECURITY_LOW)
2253 return true;
2254
2255 /* If we're encrypted with an STK but the caller prefers using
2256 * LTK claim insufficient security. This way we allow the
2257 * connection to be re-encrypted with an LTK, even if the LTK
2258 * provides the same level of security. Only exception is if we
2259 * don't have an LTK (e.g. because of key distribution bits).
2260 */
2261 if (key_pref == SMP_USE_LTK &&
2262 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
2263 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
2264 return false;
2265
2266 if (hcon->sec_level >= sec_level)
2267 return true;
2268
2269 return false;
2270 }
2271
2272 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
2273 {
2274 struct smp_cmd_security_req *rp = (void *) skb->data;
2275 struct smp_cmd_pairing cp;
2276 struct hci_conn *hcon = conn->hcon;
2277 struct hci_dev *hdev = hcon->hdev;
2278 struct smp_chan *smp;
2279 u8 sec_level, auth;
2280
2281 BT_DBG("conn %p", conn);
2282
2283 if (skb->len < sizeof(*rp))
2284 return SMP_INVALID_PARAMS;
2285
2286 if (hcon->role != HCI_ROLE_MASTER)
2287 return SMP_CMD_NOTSUPP;
2288
2289 auth = rp->auth_req & AUTH_REQ_MASK(hdev);
2290
2291 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC))
2292 return SMP_AUTH_REQUIREMENTS;
2293
2294 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
2295 sec_level = BT_SECURITY_MEDIUM;
2296 else
2297 sec_level = authreq_to_seclevel(auth);
2298
2299 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) {
2300 /* If link is already encrypted with sufficient security we
2301 * still need refresh encryption as per Core Spec 5.0 Vol 3,
2302 * Part H 2.4.6
2303 */
2304 smp_ltk_encrypt(conn, hcon->sec_level);
2305 return 0;
2306 }
2307
2308 if (sec_level > hcon->pending_sec_level)
2309 hcon->pending_sec_level = sec_level;
2310
2311 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2312 return 0;
2313
2314 smp = smp_chan_create(conn);
2315 if (!smp)
2316 return SMP_UNSPECIFIED;
2317
2318 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) &&
2319 (auth & SMP_AUTH_BONDING))
2320 return SMP_PAIRING_NOTSUPP;
2321
2322 skb_pull(skb, sizeof(*rp));
2323
2324 memset(&cp, 0, sizeof(cp));
2325 build_pairing_cmd(conn, &cp, NULL, auth);
2326
2327 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2328 memcpy(&smp->preq[1], &cp, sizeof(cp));
2329
2330 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2331 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2332
2333 return 0;
2334 }
2335
2336 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
2337 {
2338 struct l2cap_conn *conn = hcon->l2cap_data;
2339 struct l2cap_chan *chan;
2340 struct smp_chan *smp;
2341 __u8 authreq;
2342 int ret;
2343
2344 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
2345
2346 /* This may be NULL if there's an unexpected disconnection */
2347 if (!conn)
2348 return 1;
2349
2350 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED))
2351 return 1;
2352
2353 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
2354 return 1;
2355
2356 if (sec_level > hcon->pending_sec_level)
2357 hcon->pending_sec_level = sec_level;
2358
2359 if (hcon->role == HCI_ROLE_MASTER)
2360 if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
2361 return 0;
2362
2363 chan = conn->smp;
2364 if (!chan) {
2365 bt_dev_err(hcon->hdev, "security requested but not available");
2366 return 1;
2367 }
2368
2369 l2cap_chan_lock(chan);
2370
2371 /* If SMP is already in progress ignore this request */
2372 if (chan->data) {
2373 ret = 0;
2374 goto unlock;
2375 }
2376
2377 smp = smp_chan_create(conn);
2378 if (!smp) {
2379 ret = 1;
2380 goto unlock;
2381 }
2382
2383 authreq = seclevel_to_authreq(sec_level);
2384
2385 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) {
2386 authreq |= SMP_AUTH_SC;
2387 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED))
2388 authreq |= SMP_AUTH_CT2;
2389 }
2390
2391 /* Require MITM if IO Capability allows or the security level
2392 * requires it.
2393 */
2394 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
2395 hcon->pending_sec_level > BT_SECURITY_MEDIUM)
2396 authreq |= SMP_AUTH_MITM;
2397
2398 if (hcon->role == HCI_ROLE_MASTER) {
2399 struct smp_cmd_pairing cp;
2400
2401 build_pairing_cmd(conn, &cp, NULL, authreq);
2402 smp->preq[0] = SMP_CMD_PAIRING_REQ;
2403 memcpy(&smp->preq[1], &cp, sizeof(cp));
2404
2405 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
2406 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
2407 } else {
2408 struct smp_cmd_security_req cp;
2409 cp.auth_req = authreq;
2410 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
2411 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ);
2412 }
2413
2414 set_bit(SMP_FLAG_INITIATOR, &smp->flags);
2415 ret = 0;
2416
2417 unlock:
2418 l2cap_chan_unlock(chan);
2419 return ret;
2420 }
2421
2422 void smp_cancel_pairing(struct hci_conn *hcon)
2423 {
2424 struct l2cap_conn *conn = hcon->l2cap_data;
2425 struct l2cap_chan *chan;
2426 struct smp_chan *smp;
2427
2428 if (!conn)
2429 return;
2430
2431 chan = conn->smp;
2432 if (!chan)
2433 return;
2434
2435 l2cap_chan_lock(chan);
2436
2437 smp = chan->data;
2438 if (smp) {
2439 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags))
2440 smp_failure(conn, 0);
2441 else
2442 smp_failure(conn, SMP_UNSPECIFIED);
2443 }
2444
2445 l2cap_chan_unlock(chan);
2446 }
2447
2448 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
2449 {
2450 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
2451 struct l2cap_chan *chan = conn->smp;
2452 struct smp_chan *smp = chan->data;
2453
2454 BT_DBG("conn %p", conn);
2455
2456 if (skb->len < sizeof(*rp))
2457 return SMP_INVALID_PARAMS;
2458
2459 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT);
2460
2461 skb_pull(skb, sizeof(*rp));
2462
2463 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
2464
2465 return 0;
2466 }
2467
2468 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
2469 {
2470 struct smp_cmd_master_ident *rp = (void *) skb->data;
2471 struct l2cap_chan *chan = conn->smp;
2472 struct smp_chan *smp = chan->data;
2473 struct hci_dev *hdev = conn->hcon->hdev;
2474 struct hci_conn *hcon = conn->hcon;
2475 struct smp_ltk *ltk;
2476 u8 authenticated;
2477
2478 BT_DBG("conn %p", conn);
2479
2480 if (skb->len < sizeof(*rp))
2481 return SMP_INVALID_PARAMS;
2482
2483 /* Mark the information as received */
2484 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY;
2485
2486 if (smp->remote_key_dist & SMP_DIST_ID_KEY)
2487 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO);
2488 else if (smp->remote_key_dist & SMP_DIST_SIGN)
2489 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2490
2491 skb_pull(skb, sizeof(*rp));
2492
2493 authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
2494 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
2495 authenticated, smp->tk, smp->enc_key_size,
2496 rp->ediv, rp->rand);
2497 smp->ltk = ltk;
2498 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2499 smp_distribute_keys(smp);
2500
2501 return 0;
2502 }
2503
2504 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb)
2505 {
2506 struct smp_cmd_ident_info *info = (void *) skb->data;
2507 struct l2cap_chan *chan = conn->smp;
2508 struct smp_chan *smp = chan->data;
2509
2510 BT_DBG("");
2511
2512 if (skb->len < sizeof(*info))
2513 return SMP_INVALID_PARAMS;
2514
2515 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO);
2516
2517 skb_pull(skb, sizeof(*info));
2518
2519 memcpy(smp->irk, info->irk, 16);
2520
2521 return 0;
2522 }
2523
2524 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
2525 struct sk_buff *skb)
2526 {
2527 struct smp_cmd_ident_addr_info *info = (void *) skb->data;
2528 struct l2cap_chan *chan = conn->smp;
2529 struct smp_chan *smp = chan->data;
2530 struct hci_conn *hcon = conn->hcon;
2531 bdaddr_t rpa;
2532
2533 BT_DBG("");
2534
2535 if (skb->len < sizeof(*info))
2536 return SMP_INVALID_PARAMS;
2537
2538 /* Mark the information as received */
2539 smp->remote_key_dist &= ~SMP_DIST_ID_KEY;
2540
2541 if (smp->remote_key_dist & SMP_DIST_SIGN)
2542 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
2543
2544 skb_pull(skb, sizeof(*info));
2545
2546 /* Strictly speaking the Core Specification (4.1) allows sending
2547 * an empty address which would force us to rely on just the IRK
2548 * as "identity information". However, since such
2549 * implementations are not known of and in order to not over
2550 * complicate our implementation, simply pretend that we never
2551 * received an IRK for such a device.
2552 *
2553 * The Identity Address must also be a Static Random or Public
2554 * Address, which hci_is_identity_address() checks for.
2555 */
2556 if (!bacmp(&info->bdaddr, BDADDR_ANY) ||
2557 !hci_is_identity_address(&info->bdaddr, info->addr_type)) {
2558 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address");
2559 goto distribute;
2560 }
2561
2562 bacpy(&smp->id_addr, &info->bdaddr);
2563 smp->id_addr_type = info->addr_type;
2564
2565 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type))
2566 bacpy(&rpa, &hcon->dst);
2567 else
2568 bacpy(&rpa, BDADDR_ANY);
2569
2570 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr,
2571 smp->id_addr_type, smp->irk, &rpa);
2572
2573 distribute:
2574 if (!(smp->remote_key_dist & KEY_DIST_MASK))
2575 smp_distribute_keys(smp);
2576
2577 return 0;
2578 }
2579
2580 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
2581 {
2582 struct smp_cmd_sign_info *rp = (void *) skb->data;
2583 struct l2cap_chan *chan = conn->smp;
2584 struct smp_chan *smp = chan->data;
2585 struct smp_csrk *csrk;
2586
2587 BT_DBG("conn %p", conn);
2588
2589 if (skb->len < sizeof(*rp))
2590 return SMP_INVALID_PARAMS;
2591
2592 /* Mark the information as received */
2593 smp->remote_key_dist &= ~SMP_DIST_SIGN;
2594
2595 skb_pull(skb, sizeof(*rp));
2596
2597 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
2598 if (csrk) {
2599 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM)
2600 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED;
2601 else
2602 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED;
2603 memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
2604 }
2605 smp->csrk = csrk;
2606 smp_distribute_keys(smp);
2607
2608 return 0;
2609 }
2610
2611 static u8 sc_select_method(struct smp_chan *smp)
2612 {
2613 struct l2cap_conn *conn = smp->conn;
2614 struct hci_conn *hcon = conn->hcon;
2615 struct smp_cmd_pairing *local, *remote;
2616 u8 local_mitm, remote_mitm, local_io, remote_io, method;
2617
2618 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) ||
2619 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags))
2620 return REQ_OOB;
2621
2622 /* The preq/prsp contain the raw Pairing Request/Response PDUs
2623 * which are needed as inputs to some crypto functions. To get
2624 * the "struct smp_cmd_pairing" from them we need to skip the
2625 * first byte which contains the opcode.
2626 */
2627 if (hcon->out) {
2628 local = (void *) &smp->preq[1];
2629 remote = (void *) &smp->prsp[1];
2630 } else {
2631 local = (void *) &smp->prsp[1];
2632 remote = (void *) &smp->preq[1];
2633 }
2634
2635 local_io = local->io_capability;
2636 remote_io = remote->io_capability;
2637
2638 local_mitm = (local->auth_req & SMP_AUTH_MITM);
2639 remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
2640
2641 /* If either side wants MITM, look up the method from the table,
2642 * otherwise use JUST WORKS.
2643 */
2644 if (local_mitm || remote_mitm)
2645 method = get_auth_method(smp, local_io, remote_io);
2646 else
2647 method = JUST_WORKS;
2648
2649 /* Don't confirm locally initiated pairing attempts */
2650 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
2651 method = JUST_WORKS;
2652
2653 return method;
2654 }
2655
2656 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
2657 {
2658 struct smp_cmd_public_key *key = (void *) skb->data;
2659 struct hci_conn *hcon = conn->hcon;
2660 struct l2cap_chan *chan = conn->smp;
2661 struct smp_chan *smp = chan->data;
2662 struct hci_dev *hdev = hcon->hdev;
2663 struct crypto_kpp *tfm_ecdh;
2664 struct smp_cmd_pairing_confirm cfm;
2665 int err;
2666
2667 BT_DBG("conn %p", conn);
2668
2669 if (skb->len < sizeof(*key))
2670 return SMP_INVALID_PARAMS;
2671
2672 memcpy(smp->remote_pk, key, 64);
2673
2674 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) {
2675 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
2676 smp->rr, 0, cfm.confirm_val);
2677 if (err)
2678 return SMP_UNSPECIFIED;
2679
2680 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16))
2681 return SMP_CONFIRM_FAILED;
2682 }
2683
2684 /* Non-initiating device sends its public key after receiving
2685 * the key from the initiating device.
2686 */
2687 if (!hcon->out) {
2688 err = sc_send_public_key(smp);
2689 if (err)
2690 return err;
2691 }
2692
2693 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
2694 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
2695
2696 /* Compute the shared secret on the same crypto tfm on which the private
2697 * key was set/generated.
2698 */
2699 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
2700 struct smp_dev *smp_dev = chan->data;
2701
2702 tfm_ecdh = smp_dev->tfm_ecdh;
2703 } else {
2704 tfm_ecdh = smp->tfm_ecdh;
2705 }
2706
2707 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey))
2708 return SMP_UNSPECIFIED;
2709
2710 SMP_DBG("DHKey %32phN", smp->dhkey);
2711
2712 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
2713
2714 smp->method = sc_select_method(smp);
2715
2716 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
2717
2718 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
2719 if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
2720 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
2721 else
2722 hcon->pending_sec_level = BT_SECURITY_FIPS;
2723
2724 if (!crypto_memneq(debug_pk, smp->remote_pk, 64))
2725 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
2726
2727 if (smp->method == DSP_PASSKEY) {
2728 get_random_bytes(&hcon->passkey_notify,
2729 sizeof(hcon->passkey_notify));
2730 hcon->passkey_notify %= 1000000;
2731 hcon->passkey_entered = 0;
2732 smp->passkey_round = 0;
2733 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
2734 hcon->dst_type,
2735 hcon->passkey_notify,
2736 hcon->passkey_entered))
2737 return SMP_UNSPECIFIED;
2738 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2739 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
2740 }
2741
2742 if (smp->method == REQ_OOB) {
2743 if (hcon->out)
2744 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
2745 sizeof(smp->prnd), smp->prnd);
2746
2747 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2748
2749 return 0;
2750 }
2751
2752 if (hcon->out)
2753 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2754
2755 if (smp->method == REQ_PASSKEY) {
2756 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
2757 hcon->dst_type))
2758 return SMP_UNSPECIFIED;
2759 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
2760 set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
2761 return 0;
2762 }
2763
2764 /* The Initiating device waits for the non-initiating device to
2765 * send the confirm value.
2766 */
2767 if (conn->hcon->out)
2768 return 0;
2769
2770 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
2771 0, cfm.confirm_val);
2772 if (err)
2773 return SMP_UNSPECIFIED;
2774
2775 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
2776 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
2777
2778 return 0;
2779 }
2780
2781 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
2782 {
2783 struct smp_cmd_dhkey_check *check = (void *) skb->data;
2784 struct l2cap_chan *chan = conn->smp;
2785 struct hci_conn *hcon = conn->hcon;
2786 struct smp_chan *smp = chan->data;
2787 u8 a[7], b[7], *local_addr, *remote_addr;
2788 u8 io_cap[3], r[16], e[16];
2789 int err;
2790
2791 BT_DBG("conn %p", conn);
2792
2793 if (skb->len < sizeof(*check))
2794 return SMP_INVALID_PARAMS;
2795
2796 memcpy(a, &hcon->init_addr, 6);
2797 memcpy(b, &hcon->resp_addr, 6);
2798 a[6] = hcon->init_addr_type;
2799 b[6] = hcon->resp_addr_type;
2800
2801 if (hcon->out) {
2802 local_addr = a;
2803 remote_addr = b;
2804 memcpy(io_cap, &smp->prsp[1], 3);
2805 } else {
2806 local_addr = b;
2807 remote_addr = a;
2808 memcpy(io_cap, &smp->preq[1], 3);
2809 }
2810
2811 memset(r, 0, sizeof(r));
2812
2813 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
2814 put_unaligned_le32(hcon->passkey_notify, r);
2815 else if (smp->method == REQ_OOB)
2816 memcpy(r, smp->lr, 16);
2817
2818 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
2819 io_cap, remote_addr, local_addr, e);
2820 if (err)
2821 return SMP_UNSPECIFIED;
2822
2823 if (crypto_memneq(check->e, e, 16))
2824 return SMP_DHKEY_CHECK_FAILED;
2825
2826 if (!hcon->out) {
2827 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
2828 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
2829 return 0;
2830 }
2831
2832 /* Slave sends DHKey check as response to master */
2833 sc_dhkey_check(smp);
2834 }
2835
2836 sc_add_ltk(smp);
2837
2838 if (hcon->out) {
2839 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size);
2840 hcon->enc_key_size = smp->enc_key_size;
2841 }
2842
2843 return 0;
2844 }
2845
2846 static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
2847 struct sk_buff *skb)
2848 {
2849 struct smp_cmd_keypress_notify *kp = (void *) skb->data;
2850
2851 BT_DBG("value 0x%02x", kp->value);
2852
2853 return 0;
2854 }
2855
2856 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
2857 {
2858 struct l2cap_conn *conn = chan->conn;
2859 struct hci_conn *hcon = conn->hcon;
2860 struct smp_chan *smp;
2861 __u8 code, reason;
2862 int err = 0;
2863
2864 if (skb->len < 1)
2865 return -EILSEQ;
2866
2867 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) {
2868 reason = SMP_PAIRING_NOTSUPP;
2869 goto done;
2870 }
2871
2872 code = skb->data[0];
2873 skb_pull(skb, sizeof(code));
2874
2875 smp = chan->data;
2876
2877 if (code > SMP_CMD_MAX)
2878 goto drop;
2879
2880 if (smp && !test_and_clear_bit(code, &smp->allow_cmd))
2881 goto drop;
2882
2883 /* If we don't have a context the only allowed commands are
2884 * pairing request and security request.
2885 */
2886 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ)
2887 goto drop;
2888
2889 switch (code) {
2890 case SMP_CMD_PAIRING_REQ:
2891 reason = smp_cmd_pairing_req(conn, skb);
2892 break;
2893
2894 case SMP_CMD_PAIRING_FAIL:
2895 smp_failure(conn, 0);
2896 err = -EPERM;
2897 break;
2898
2899 case SMP_CMD_PAIRING_RSP:
2900 reason = smp_cmd_pairing_rsp(conn, skb);
2901 break;
2902
2903 case SMP_CMD_SECURITY_REQ:
2904 reason = smp_cmd_security_req(conn, skb);
2905 break;
2906
2907 case SMP_CMD_PAIRING_CONFIRM:
2908 reason = smp_cmd_pairing_confirm(conn, skb);
2909 break;
2910
2911 case SMP_CMD_PAIRING_RANDOM:
2912 reason = smp_cmd_pairing_random(conn, skb);
2913 break;
2914
2915 case SMP_CMD_ENCRYPT_INFO:
2916 reason = smp_cmd_encrypt_info(conn, skb);
2917 break;
2918
2919 case SMP_CMD_MASTER_IDENT:
2920 reason = smp_cmd_master_ident(conn, skb);
2921 break;
2922
2923 case SMP_CMD_IDENT_INFO:
2924 reason = smp_cmd_ident_info(conn, skb);
2925 break;
2926
2927 case SMP_CMD_IDENT_ADDR_INFO:
2928 reason = smp_cmd_ident_addr_info(conn, skb);
2929 break;
2930
2931 case SMP_CMD_SIGN_INFO:
2932 reason = smp_cmd_sign_info(conn, skb);
2933 break;
2934
2935 case SMP_CMD_PUBLIC_KEY:
2936 reason = smp_cmd_public_key(conn, skb);
2937 break;
2938
2939 case SMP_CMD_DHKEY_CHECK:
2940 reason = smp_cmd_dhkey_check(conn, skb);
2941 break;
2942
2943 case SMP_CMD_KEYPRESS_NOTIFY:
2944 reason = smp_cmd_keypress_notify(conn, skb);
2945 break;
2946
2947 default:
2948 BT_DBG("Unknown command code 0x%2.2x", code);
2949 reason = SMP_CMD_NOTSUPP;
2950 goto done;
2951 }
2952
2953 done:
2954 if (!err) {
2955 if (reason)
2956 smp_failure(conn, reason);
2957 kfree_skb(skb);
2958 }
2959
2960 return err;
2961
2962 drop:
2963 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR",
2964 code, &hcon->dst);
2965 kfree_skb(skb);
2966 return 0;
2967 }
2968
2969 static void smp_teardown_cb(struct l2cap_chan *chan, int err)
2970 {
2971 struct l2cap_conn *conn = chan->conn;
2972
2973 BT_DBG("chan %p", chan);
2974
2975 if (chan->data)
2976 smp_chan_destroy(conn);
2977
2978 conn->smp = NULL;
2979 l2cap_chan_put(chan);
2980 }
2981
2982 static void bredr_pairing(struct l2cap_chan *chan)
2983 {
2984 struct l2cap_conn *conn = chan->conn;
2985 struct hci_conn *hcon = conn->hcon;
2986 struct hci_dev *hdev = hcon->hdev;
2987 struct smp_cmd_pairing req;
2988 struct smp_chan *smp;
2989
2990 BT_DBG("chan %p", chan);
2991
2992 /* Only new pairings are interesting */
2993 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
2994 return;
2995
2996 /* Don't bother if we're not encrypted */
2997 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
2998 return;
2999
3000 /* Only master may initiate SMP over BR/EDR */
3001 if (hcon->role != HCI_ROLE_MASTER)
3002 return;
3003
3004 /* Secure Connections support must be enabled */
3005 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED))
3006 return;
3007
3008 /* BR/EDR must use Secure Connections for SMP */
3009 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
3010 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3011 return;
3012
3013 /* If our LE support is not enabled don't do anything */
3014 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED))
3015 return;
3016
3017 /* Don't bother if remote LE support is not enabled */
3018 if (!lmp_host_le_capable(hcon))
3019 return;
3020
3021 /* Remote must support SMP fixed chan for BR/EDR */
3022 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
3023 return;
3024
3025 /* Don't bother if SMP is already ongoing */
3026 if (chan->data)
3027 return;
3028
3029 smp = smp_chan_create(conn);
3030 if (!smp) {
3031 bt_dev_err(hdev, "unable to create SMP context for BR/EDR");
3032 return;
3033 }
3034
3035 set_bit(SMP_FLAG_SC, &smp->flags);
3036
3037 BT_DBG("%s starting SMP over BR/EDR", hdev->name);
3038
3039 /* Prepare and send the BR/EDR SMP Pairing Request */
3040 build_bredr_pairing_cmd(smp, &req, NULL);
3041
3042 smp->preq[0] = SMP_CMD_PAIRING_REQ;
3043 memcpy(&smp->preq[1], &req, sizeof(req));
3044
3045 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
3046 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
3047 }
3048
3049 static void smp_resume_cb(struct l2cap_chan *chan)
3050 {
3051 struct smp_chan *smp = chan->data;
3052 struct l2cap_conn *conn = chan->conn;
3053 struct hci_conn *hcon = conn->hcon;
3054
3055 BT_DBG("chan %p", chan);
3056
3057 if (hcon->type == ACL_LINK) {
3058 bredr_pairing(chan);
3059 return;
3060 }
3061
3062 if (!smp)
3063 return;
3064
3065 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3066 return;
3067
3068 cancel_delayed_work(&smp->security_timer);
3069
3070 smp_distribute_keys(smp);
3071 }
3072
3073 static void smp_ready_cb(struct l2cap_chan *chan)
3074 {
3075 struct l2cap_conn *conn = chan->conn;
3076 struct hci_conn *hcon = conn->hcon;
3077
3078 BT_DBG("chan %p", chan);
3079
3080 /* No need to call l2cap_chan_hold() here since we already own
3081 * the reference taken in smp_new_conn_cb(). This is just the
3082 * first time that we tie it to a specific pointer. The code in
3083 * l2cap_core.c ensures that there's no risk this function wont
3084 * get called if smp_new_conn_cb was previously called.
3085 */
3086 conn->smp = chan;
3087
3088 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
3089 bredr_pairing(chan);
3090 }
3091
3092 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
3093 {
3094 int err;
3095
3096 BT_DBG("chan %p", chan);
3097
3098 err = smp_sig_channel(chan, skb);
3099 if (err) {
3100 struct smp_chan *smp = chan->data;
3101
3102 if (smp)
3103 cancel_delayed_work_sync(&smp->security_timer);
3104
3105 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE);
3106 }
3107
3108 return err;
3109 }
3110
3111 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan,
3112 unsigned long hdr_len,
3113 unsigned long len, int nb)
3114 {
3115 struct sk_buff *skb;
3116
3117 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
3118 if (!skb)
3119 return ERR_PTR(-ENOMEM);
3120
3121 skb->priority = HCI_PRIO_MAX;
3122 bt_cb(skb)->l2cap.chan = chan;
3123
3124 return skb;
3125 }
3126
3127 static const struct l2cap_ops smp_chan_ops = {
3128 .name = "Security Manager",
3129 .ready = smp_ready_cb,
3130 .recv = smp_recv_cb,
3131 .alloc_skb = smp_alloc_skb_cb,
3132 .teardown = smp_teardown_cb,
3133 .resume = smp_resume_cb,
3134
3135 .new_connection = l2cap_chan_no_new_connection,
3136 .state_change = l2cap_chan_no_state_change,
3137 .close = l2cap_chan_no_close,
3138 .defer = l2cap_chan_no_defer,
3139 .suspend = l2cap_chan_no_suspend,
3140 .set_shutdown = l2cap_chan_no_set_shutdown,
3141 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3142 };
3143
3144 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
3145 {
3146 struct l2cap_chan *chan;
3147
3148 BT_DBG("pchan %p", pchan);
3149
3150 chan = l2cap_chan_create();
3151 if (!chan)
3152 return NULL;
3153
3154 chan->chan_type = pchan->chan_type;
3155 chan->ops = &smp_chan_ops;
3156 chan->scid = pchan->scid;
3157 chan->dcid = chan->scid;
3158 chan->imtu = pchan->imtu;
3159 chan->omtu = pchan->omtu;
3160 chan->mode = pchan->mode;
3161
3162 /* Other L2CAP channels may request SMP routines in order to
3163 * change the security level. This means that the SMP channel
3164 * lock must be considered in its own category to avoid lockdep
3165 * warnings.
3166 */
3167 atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
3168
3169 BT_DBG("created chan %p", chan);
3170
3171 return chan;
3172 }
3173
3174 static const struct l2cap_ops smp_root_chan_ops = {
3175 .name = "Security Manager Root",
3176 .new_connection = smp_new_conn_cb,
3177
3178 /* None of these are implemented for the root channel */
3179 .close = l2cap_chan_no_close,
3180 .alloc_skb = l2cap_chan_no_alloc_skb,
3181 .recv = l2cap_chan_no_recv,
3182 .state_change = l2cap_chan_no_state_change,
3183 .teardown = l2cap_chan_no_teardown,
3184 .ready = l2cap_chan_no_ready,
3185 .defer = l2cap_chan_no_defer,
3186 .suspend = l2cap_chan_no_suspend,
3187 .resume = l2cap_chan_no_resume,
3188 .set_shutdown = l2cap_chan_no_set_shutdown,
3189 .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
3190 };
3191
3192 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
3193 {
3194 struct l2cap_chan *chan;
3195 struct smp_dev *smp;
3196 struct crypto_cipher *tfm_aes;
3197 struct crypto_shash *tfm_cmac;
3198 struct crypto_kpp *tfm_ecdh;
3199
3200 if (cid == L2CAP_CID_SMP_BREDR) {
3201 smp = NULL;
3202 goto create_chan;
3203 }
3204
3205 smp = kzalloc(sizeof(*smp), GFP_KERNEL);
3206 if (!smp)
3207 return ERR_PTR(-ENOMEM);
3208
3209 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3210 if (IS_ERR(tfm_aes)) {
3211 BT_ERR("Unable to create AES crypto context");
3212 kzfree(smp);
3213 return ERR_CAST(tfm_aes);
3214 }
3215
3216 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0);
3217 if (IS_ERR(tfm_cmac)) {
3218 BT_ERR("Unable to create CMAC crypto context");
3219 crypto_free_cipher(tfm_aes);
3220 kzfree(smp);
3221 return ERR_CAST(tfm_cmac);
3222 }
3223
3224 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0);
3225 if (IS_ERR(tfm_ecdh)) {
3226 BT_ERR("Unable to create ECDH crypto context");
3227 crypto_free_shash(tfm_cmac);
3228 crypto_free_cipher(tfm_aes);
3229 kzfree(smp);
3230 return ERR_CAST(tfm_ecdh);
3231 }
3232
3233 smp->tfm_aes = tfm_aes;
3234 smp->tfm_cmac = tfm_cmac;
3235 smp->tfm_ecdh = tfm_ecdh;
3236 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE;
3237 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
3238
3239 create_chan:
3240 chan = l2cap_chan_create();
3241 if (!chan) {
3242 if (smp) {
3243 crypto_free_cipher(smp->tfm_aes);
3244 crypto_free_shash(smp->tfm_cmac);
3245 crypto_free_kpp(smp->tfm_ecdh);
3246 kzfree(smp);
3247 }
3248 return ERR_PTR(-ENOMEM);
3249 }
3250
3251 chan->data = smp;
3252
3253 l2cap_add_scid(chan, cid);
3254
3255 l2cap_chan_set_defaults(chan);
3256
3257 if (cid == L2CAP_CID_SMP) {
3258 u8 bdaddr_type;
3259
3260 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type);
3261
3262 if (bdaddr_type == ADDR_LE_DEV_PUBLIC)
3263 chan->src_type = BDADDR_LE_PUBLIC;
3264 else
3265 chan->src_type = BDADDR_LE_RANDOM;
3266 } else {
3267 bacpy(&chan->src, &hdev->bdaddr);
3268 chan->src_type = BDADDR_BREDR;
3269 }
3270
3271 chan->state = BT_LISTEN;
3272 chan->mode = L2CAP_MODE_BASIC;
3273 chan->imtu = L2CAP_DEFAULT_MTU;
3274 chan->ops = &smp_root_chan_ops;
3275
3276 /* Set correct nesting level for a parent/listening channel */
3277 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
3278
3279 return chan;
3280 }
3281
3282 static void smp_del_chan(struct l2cap_chan *chan)
3283 {
3284 struct smp_dev *smp;
3285
3286 BT_DBG("chan %p", chan);
3287
3288 smp = chan->data;
3289 if (smp) {
3290 chan->data = NULL;
3291 crypto_free_cipher(smp->tfm_aes);
3292 crypto_free_shash(smp->tfm_cmac);
3293 crypto_free_kpp(smp->tfm_ecdh);
3294 kzfree(smp);
3295 }
3296
3297 l2cap_chan_put(chan);
3298 }
3299
3300 static ssize_t force_bredr_smp_read(struct file *file,
3301 char __user *user_buf,
3302 size_t count, loff_t *ppos)
3303 {
3304 struct hci_dev *hdev = file->private_data;
3305 char buf[3];
3306
3307 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N';
3308 buf[1] = '\n';
3309 buf[2] = '\0';
3310 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
3311 }
3312
3313 static ssize_t force_bredr_smp_write(struct file *file,
3314 const char __user *user_buf,
3315 size_t count, loff_t *ppos)
3316 {
3317 struct hci_dev *hdev = file->private_data;
3318 char buf[32];
3319 size_t buf_size = min(count, (sizeof(buf)-1));
3320 bool enable;
3321
3322 if (copy_from_user(buf, user_buf, buf_size))
3323 return -EFAULT;
3324
3325 buf[buf_size] = '\0';
3326 if (strtobool(buf, &enable))
3327 return -EINVAL;
3328
3329 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3330 return -EALREADY;
3331
3332 if (enable) {
3333 struct l2cap_chan *chan;
3334
3335 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3336 if (IS_ERR(chan))
3337 return PTR_ERR(chan);
3338
3339 hdev->smp_bredr_data = chan;
3340 } else {
3341 struct l2cap_chan *chan;
3342
3343 chan = hdev->smp_bredr_data;
3344 hdev->smp_bredr_data = NULL;
3345 smp_del_chan(chan);
3346 }
3347
3348 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP);
3349
3350 return count;
3351 }
3352
3353 static const struct file_operations force_bredr_smp_fops = {
3354 .open = simple_open,
3355 .read = force_bredr_smp_read,
3356 .write = force_bredr_smp_write,
3357 .llseek = default_llseek,
3358 };
3359
3360 static ssize_t le_min_key_size_read(struct file *file,
3361 char __user *user_buf,
3362 size_t count, loff_t *ppos)
3363 {
3364 struct hci_dev *hdev = file->private_data;
3365 char buf[4];
3366
3367 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size);
3368
3369 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3370 }
3371
3372 static ssize_t le_min_key_size_write(struct file *file,
3373 const char __user *user_buf,
3374 size_t count, loff_t *ppos)
3375 {
3376 struct hci_dev *hdev = file->private_data;
3377 char buf[32];
3378 size_t buf_size = min(count, (sizeof(buf) - 1));
3379 u8 key_size;
3380
3381 if (copy_from_user(buf, user_buf, buf_size))
3382 return -EFAULT;
3383
3384 buf[buf_size] = '\0';
3385
3386 sscanf(buf, "%hhu", &key_size);
3387
3388 if (key_size > SMP_DEV(hdev)->max_key_size ||
3389 key_size < SMP_MIN_ENC_KEY_SIZE)
3390 return -EINVAL;
3391
3392 SMP_DEV(hdev)->min_key_size = key_size;
3393
3394 return count;
3395 }
3396
3397 static const struct file_operations le_min_key_size_fops = {
3398 .open = simple_open,
3399 .read = le_min_key_size_read,
3400 .write = le_min_key_size_write,
3401 .llseek = default_llseek,
3402 };
3403
3404 static ssize_t le_max_key_size_read(struct file *file,
3405 char __user *user_buf,
3406 size_t count, loff_t *ppos)
3407 {
3408 struct hci_dev *hdev = file->private_data;
3409 char buf[4];
3410
3411 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size);
3412
3413 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
3414 }
3415
3416 static ssize_t le_max_key_size_write(struct file *file,
3417 const char __user *user_buf,
3418 size_t count, loff_t *ppos)
3419 {
3420 struct hci_dev *hdev = file->private_data;
3421 char buf[32];
3422 size_t buf_size = min(count, (sizeof(buf) - 1));
3423 u8 key_size;
3424
3425 if (copy_from_user(buf, user_buf, buf_size))
3426 return -EFAULT;
3427
3428 buf[buf_size] = '\0';
3429
3430 sscanf(buf, "%hhu", &key_size);
3431
3432 if (key_size > SMP_MAX_ENC_KEY_SIZE ||
3433 key_size < SMP_DEV(hdev)->min_key_size)
3434 return -EINVAL;
3435
3436 SMP_DEV(hdev)->max_key_size = key_size;
3437
3438 return count;
3439 }
3440
3441 static const struct file_operations le_max_key_size_fops = {
3442 .open = simple_open,
3443 .read = le_max_key_size_read,
3444 .write = le_max_key_size_write,
3445 .llseek = default_llseek,
3446 };
3447
3448 int smp_register(struct hci_dev *hdev)
3449 {
3450 struct l2cap_chan *chan;
3451
3452 BT_DBG("%s", hdev->name);
3453
3454 /* If the controller does not support Low Energy operation, then
3455 * there is also no need to register any SMP channel.
3456 */
3457 if (!lmp_le_capable(hdev))
3458 return 0;
3459
3460 if (WARN_ON(hdev->smp_data)) {
3461 chan = hdev->smp_data;
3462 hdev->smp_data = NULL;
3463 smp_del_chan(chan);
3464 }
3465
3466 chan = smp_add_cid(hdev, L2CAP_CID_SMP);
3467 if (IS_ERR(chan))
3468 return PTR_ERR(chan);
3469
3470 hdev->smp_data = chan;
3471
3472 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev,
3473 &le_min_key_size_fops);
3474 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev,
3475 &le_max_key_size_fops);
3476
3477 /* If the controller does not support BR/EDR Secure Connections
3478 * feature, then the BR/EDR SMP channel shall not be present.
3479 *
3480 * To test this with Bluetooth 4.0 controllers, create a debugfs
3481 * switch that allows forcing BR/EDR SMP support and accepting
3482 * cross-transport pairing on non-AES encrypted connections.
3483 */
3484 if (!lmp_sc_capable(hdev)) {
3485 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs,
3486 hdev, &force_bredr_smp_fops);
3487
3488 /* Flag can be already set here (due to power toggle) */
3489 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
3490 return 0;
3491 }
3492
3493 if (WARN_ON(hdev->smp_bredr_data)) {
3494 chan = hdev->smp_bredr_data;
3495 hdev->smp_bredr_data = NULL;
3496 smp_del_chan(chan);
3497 }
3498
3499 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
3500 if (IS_ERR(chan)) {
3501 int err = PTR_ERR(chan);
3502 chan = hdev->smp_data;
3503 hdev->smp_data = NULL;
3504 smp_del_chan(chan);
3505 return err;
3506 }
3507
3508 hdev->smp_bredr_data = chan;
3509
3510 return 0;
3511 }
3512
3513 void smp_unregister(struct hci_dev *hdev)
3514 {
3515 struct l2cap_chan *chan;
3516
3517 if (hdev->smp_bredr_data) {
3518 chan = hdev->smp_bredr_data;
3519 hdev->smp_bredr_data = NULL;
3520 smp_del_chan(chan);
3521 }
3522
3523 if (hdev->smp_data) {
3524 chan = hdev->smp_data;
3525 hdev->smp_data = NULL;
3526 smp_del_chan(chan);
3527 }
3528 }
3529
3530 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
3531
3532 static int __init test_debug_key(struct crypto_kpp *tfm_ecdh)
3533 {
3534 u8 pk[64];
3535 int err;
3536
3537 err = set_ecdh_privkey(tfm_ecdh, debug_sk);
3538 if (err)
3539 return err;
3540
3541 err = generate_ecdh_public_key(tfm_ecdh, pk);
3542 if (err)
3543 return err;
3544
3545 if (crypto_memneq(pk, debug_pk, 64))
3546 return -EINVAL;
3547
3548 return 0;
3549 }
3550
3551 static int __init test_ah(struct crypto_cipher *tfm_aes)
3552 {
3553 const u8 irk[16] = {
3554 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3555 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3556 const u8 r[3] = { 0x94, 0x81, 0x70 };
3557 const u8 exp[3] = { 0xaa, 0xfb, 0x0d };
3558 u8 res[3];
3559 int err;
3560
3561 err = smp_ah(tfm_aes, irk, r, res);
3562 if (err)
3563 return err;
3564
3565 if (crypto_memneq(res, exp, 3))
3566 return -EINVAL;
3567
3568 return 0;
3569 }
3570
3571 static int __init test_c1(struct crypto_cipher *tfm_aes)
3572 {
3573 const u8 k[16] = {
3574 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3575 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3576 const u8 r[16] = {
3577 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63,
3578 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 };
3579 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 };
3580 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 };
3581 const u8 _iat = 0x01;
3582 const u8 _rat = 0x00;
3583 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } };
3584 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } };
3585 const u8 exp[16] = {
3586 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2,
3587 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e };
3588 u8 res[16];
3589 int err;
3590
3591 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res);
3592 if (err)
3593 return err;
3594
3595 if (crypto_memneq(res, exp, 16))
3596 return -EINVAL;
3597
3598 return 0;
3599 }
3600
3601 static int __init test_s1(struct crypto_cipher *tfm_aes)
3602 {
3603 const u8 k[16] = {
3604 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
3605 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
3606 const u8 r1[16] = {
3607 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 };
3608 const u8 r2[16] = {
3609 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 };
3610 const u8 exp[16] = {
3611 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b,
3612 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a };
3613 u8 res[16];
3614 int err;
3615
3616 err = smp_s1(tfm_aes, k, r1, r2, res);
3617 if (err)
3618 return err;
3619
3620 if (crypto_memneq(res, exp, 16))
3621 return -EINVAL;
3622
3623 return 0;
3624 }
3625
3626 static int __init test_f4(struct crypto_shash *tfm_cmac)
3627 {
3628 const u8 u[32] = {
3629 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3630 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3631 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3632 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3633 const u8 v[32] = {
3634 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3635 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3636 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3637 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3638 const u8 x[16] = {
3639 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3640 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3641 const u8 z = 0x00;
3642 const u8 exp[16] = {
3643 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1,
3644 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 };
3645 u8 res[16];
3646 int err;
3647
3648 err = smp_f4(tfm_cmac, u, v, x, z, res);
3649 if (err)
3650 return err;
3651
3652 if (crypto_memneq(res, exp, 16))
3653 return -EINVAL;
3654
3655 return 0;
3656 }
3657
3658 static int __init test_f5(struct crypto_shash *tfm_cmac)
3659 {
3660 const u8 w[32] = {
3661 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86,
3662 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99,
3663 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3664 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3665 const u8 n1[16] = {
3666 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3667 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3668 const u8 n2[16] = {
3669 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3670 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3671 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3672 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3673 const u8 exp_ltk[16] = {
3674 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98,
3675 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 };
3676 const u8 exp_mackey[16] = {
3677 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3678 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3679 u8 mackey[16], ltk[16];
3680 int err;
3681
3682 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk);
3683 if (err)
3684 return err;
3685
3686 if (crypto_memneq(mackey, exp_mackey, 16))
3687 return -EINVAL;
3688
3689 if (crypto_memneq(ltk, exp_ltk, 16))
3690 return -EINVAL;
3691
3692 return 0;
3693 }
3694
3695 static int __init test_f6(struct crypto_shash *tfm_cmac)
3696 {
3697 const u8 w[16] = {
3698 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd,
3699 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 };
3700 const u8 n1[16] = {
3701 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3702 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3703 const u8 n2[16] = {
3704 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3705 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3706 const u8 r[16] = {
3707 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08,
3708 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 };
3709 const u8 io_cap[3] = { 0x02, 0x01, 0x01 };
3710 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 };
3711 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 };
3712 const u8 exp[16] = {
3713 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2,
3714 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 };
3715 u8 res[16];
3716 int err;
3717
3718 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res);
3719 if (err)
3720 return err;
3721
3722 if (crypto_memneq(res, exp, 16))
3723 return -EINVAL;
3724
3725 return 0;
3726 }
3727
3728 static int __init test_g2(struct crypto_shash *tfm_cmac)
3729 {
3730 const u8 u[32] = {
3731 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
3732 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
3733 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
3734 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 };
3735 const u8 v[32] = {
3736 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b,
3737 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59,
3738 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90,
3739 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 };
3740 const u8 x[16] = {
3741 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff,
3742 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 };
3743 const u8 y[16] = {
3744 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21,
3745 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 };
3746 const u32 exp_val = 0x2f9ed5ba % 1000000;
3747 u32 val;
3748 int err;
3749
3750 err = smp_g2(tfm_cmac, u, v, x, y, &val);
3751 if (err)
3752 return err;
3753
3754 if (val != exp_val)
3755 return -EINVAL;
3756
3757 return 0;
3758 }
3759
3760 static int __init test_h6(struct crypto_shash *tfm_cmac)
3761 {
3762 const u8 w[16] = {
3763 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34,
3764 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec };
3765 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c };
3766 const u8 exp[16] = {
3767 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8,
3768 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d };
3769 u8 res[16];
3770 int err;
3771
3772 err = smp_h6(tfm_cmac, w, key_id, res);
3773 if (err)
3774 return err;
3775
3776 if (crypto_memneq(res, exp, 16))
3777 return -EINVAL;
3778
3779 return 0;
3780 }
3781
3782 static char test_smp_buffer[32];
3783
3784 static ssize_t test_smp_read(struct file *file, char __user *user_buf,
3785 size_t count, loff_t *ppos)
3786 {
3787 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer,
3788 strlen(test_smp_buffer));
3789 }
3790
3791 static const struct file_operations test_smp_fops = {
3792 .open = simple_open,
3793 .read = test_smp_read,
3794 .llseek = default_llseek,
3795 };
3796
3797 static int __init run_selftests(struct crypto_cipher *tfm_aes,
3798 struct crypto_shash *tfm_cmac,
3799 struct crypto_kpp *tfm_ecdh)
3800 {
3801 ktime_t calltime, delta, rettime;
3802 unsigned long long duration;
3803 int err;
3804
3805 calltime = ktime_get();
3806
3807 err = test_debug_key(tfm_ecdh);
3808 if (err) {
3809 BT_ERR("debug_key test failed");
3810 goto done;
3811 }
3812
3813 err = test_ah(tfm_aes);
3814 if (err) {
3815 BT_ERR("smp_ah test failed");
3816 goto done;
3817 }
3818
3819 err = test_c1(tfm_aes);
3820 if (err) {
3821 BT_ERR("smp_c1 test failed");
3822 goto done;
3823 }
3824
3825 err = test_s1(tfm_aes);
3826 if (err) {
3827 BT_ERR("smp_s1 test failed");
3828 goto done;
3829 }
3830
3831 err = test_f4(tfm_cmac);
3832 if (err) {
3833 BT_ERR("smp_f4 test failed");
3834 goto done;
3835 }
3836
3837 err = test_f5(tfm_cmac);
3838 if (err) {
3839 BT_ERR("smp_f5 test failed");
3840 goto done;
3841 }
3842
3843 err = test_f6(tfm_cmac);
3844 if (err) {
3845 BT_ERR("smp_f6 test failed");
3846 goto done;
3847 }
3848
3849 err = test_g2(tfm_cmac);
3850 if (err) {
3851 BT_ERR("smp_g2 test failed");
3852 goto done;
3853 }
3854
3855 err = test_h6(tfm_cmac);
3856 if (err) {
3857 BT_ERR("smp_h6 test failed");
3858 goto done;
3859 }
3860
3861 rettime = ktime_get();
3862 delta = ktime_sub(rettime, calltime);
3863 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
3864
3865 BT_INFO("SMP test passed in %llu usecs", duration);
3866
3867 done:
3868 if (!err)
3869 snprintf(test_smp_buffer, sizeof(test_smp_buffer),
3870 "PASS (%llu usecs)\n", duration);
3871 else
3872 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n");
3873
3874 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL,
3875 &test_smp_fops);
3876
3877 return err;
3878 }
3879
3880 int __init bt_selftest_smp(void)
3881 {
3882 struct crypto_cipher *tfm_aes;
3883 struct crypto_shash *tfm_cmac;
3884 struct crypto_kpp *tfm_ecdh;
3885 int err;
3886
3887 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
3888 if (IS_ERR(tfm_aes)) {
3889 BT_ERR("Unable to create AES crypto context");
3890 return PTR_ERR(tfm_aes);
3891 }
3892
3893 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
3894 if (IS_ERR(tfm_cmac)) {
3895 BT_ERR("Unable to create CMAC crypto context");
3896 crypto_free_cipher(tfm_aes);
3897 return PTR_ERR(tfm_cmac);
3898 }
3899
3900 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0);
3901 if (IS_ERR(tfm_ecdh)) {
3902 BT_ERR("Unable to create ECDH crypto context");
3903 crypto_free_shash(tfm_cmac);
3904 crypto_free_cipher(tfm_aes);
3905 return PTR_ERR(tfm_ecdh);
3906 }
3907
3908 err = run_selftests(tfm_aes, tfm_cmac, tfm_ecdh);
3909
3910 crypto_free_shash(tfm_cmac);
3911 crypto_free_cipher(tfm_aes);
3912 crypto_free_kpp(tfm_ecdh);
3913
3914 return err;
3915 }
3916
3917 #endif
ubuntu-bionic-kernel mirror